iccprofile: Decode 'dict' data type

[deark.git] / modules / bmff.c

// This file is part of Deark.
// Copyright (C) 2016-2018 Jason Summers
// See the file COPYING for terms of use.

// ISO Base Media File Format, and related formats
// (JPEG 2000, MP4, QuickTime, etc.)

#include <deark-config.h>
#include <deark-private.h>
#include <deark-fmtutil.h>

// TODO: Rethink how to subdivide these formats into modules.
DE_DECLARE_MODULE(de_module_bmff);
DE_DECLARE_MODULE(de_module_jpeg2000);

typedef struct localctx_struct {
        u32 major_brand;
        u8 is_bmff;
        u8 is_jp2_jpx_jpm, is_jpx, is_jpm;
        u8 is_mj2;
        u8 is_heif;
        u8 is_jpegxt;
        i64 max_entries_to_print;

        u8 exif_item_id_known;
        unsigned int exif_item_id;
        i64 exif_item_offs;
        i64 exif_item_len;
} lctx;

typedef void (*handler_fn_type)(deark *c, lctx *d, struct de_boxesctx *bctx);

struct box_type_info {
        u32 boxtype;
        // flags1 is intended to be used to indicate which formats/brands use this box.
        // 0x00000001 = Generic BMFF (isom brand, etc.)
        // 0x00000008 = MJ2
        // 0x00010000 = JP2/JPX/JPM
        // 0x00040000 = JPEG XT
        // 0x00080000 = HEIF
        // 0x01000000 = Used in ilst boxes
        u32 flags1;
        // flags2: 0x1 = is_superbox
        // flags2: 0x2 = critical top-level box (used for format identification)
        u32 flags2;
        const char *name;
        handler_fn_type hfn;
};

#define BRAND_heic 0x68656963U
#define BRAND_isom 0x69736f6dU
#define BRAND_mif1 0x6d696631U
#define BRAND_mp41 0x6d703431U
#define BRAND_mp42 0x6d703432U
#define BRAND_M4A  0x4d344120U
#define BRAND_jp2  0x6a703220U
#define BRAND_jpm  0x6a706d20U
#define BRAND_jpx  0x6a707820U
#define BRAND_mjp2 0x6d6a7032U
#define BRAND_mj2s 0x6d6a3273U
#define BRAND_qt   0x71742020U

#define BOX_alis 0x616c6973U
#define BOX_auxC 0x61757843U
#define BOX_co64 0x636f3634U
#define BOX_ctts 0x63747473U
#define BOX_data 0x64617461U
#define BOX_elst 0x656c7374U
#define BOX_ftyp 0x66747970U
#define BOX_grpl 0x6772706cU
#define BOX_hvcC 0x68766343U
#define BOX_idat 0x69646174U
#define BOX_iinf 0x69696e66U
#define BOX_iloc 0x696c6f63U
#define BOX_ilst 0x696c7374U
#define BOX_infe 0x696e6665U
#define BOX_iods 0x696f6473U
#define BOX_ipco 0x6970636fU
#define BOX_ipma 0x69706d61U
#define BOX_ipro 0x6970726fU
#define BOX_iprp 0x69707270U
#define BOX_iref 0x69726566U
#define BOX_ispe 0x69737065U
#define BOX_jP   0x6a502020U
#define BOX_jp2c 0x6a703263U
#define BOX_load 0x6c6f6164U
#define BOX_mdat 0x6d646174U
#define BOX_mdhd 0x6d646864U
#define BOX_mvhd 0x6d766864U
#define BOX_name 0x6e616d65U
#define BOX_pitm 0x7069746dU
#define BOX_pnot 0x706e6f74U
#define BOX_rsrc 0x72737263U
#define BOX_sbgp 0x73626770U
#define BOX_sdtp 0x73647470U
#define BOX_sgpd 0x73677064U
#define BOX_stsd 0x73747364U
#define BOX_tkhd 0x746b6864U
#define BOX_uuid 0x75756964U
#define BOX_wide 0x77696465U
#define BOX_xml  0x786d6c20U
#define BOX_PICT 0x50494354U
#define BOX_THMB 0x54484d42U
#define BOX_PRVW 0x50525657U

#define BOX_blank 0x2d2d2d2dU // "----"
#define BOX_cpil 0x6370696cU
#define BOX_gnre 0x676e7265U
#define BOX_tmpo 0x746d706fU
#define BOX_a9ART 0xa9415254U
#define BOX_a9cmt 0xa9636d74U
#define BOX_a9nam 0xa96e616dU
#define BOX_a9too 0xa9746f6fU

// JP2:
#define BOX_cdef 0x63646566U
#define BOX_colr 0x636f6c72U
#define BOX_jp2h 0x6a703268U
#define BOX_ihdr 0x69686472U
#define BOX_res  0x72657320U
#define BOX_resc 0x72657363U
#define BOX_resd 0x72657364U
#define BOX_uinf 0x75696e66U
#define BOX_ulst 0x756c7374U
#define BOX_url  0x75726c20U
// JPX:
#define BOX_jpch 0x6a706368U
#define BOX_jplh 0x6a706c68U
#define BOX_cgrp 0x63677270U
#define BOX_ftbl 0x6674626cU
#define BOX_comp 0x636f6d70U
#define BOX_asoc 0x61736f63U
#define BOX_drep 0x64726570U
#define BOX_dtbl 0x6474626cU
#define BOX_flst 0x666c7374U
#define BOX_lbl  0x6c626c20U
#define BOX_nlst 0x6e6c7374U
#define BOX_rreq 0x72726571U
//  JPM:
#define BOX_page 0x70616765U
#define BOX_lobj 0x6c6f626aU
#define BOX_objc 0x6f626a63U
#define BOX_sdat 0x73646174U
#define BOX_mhdr 0x6d686472U
#define BOX_lhdr 0x6c686472U
#define BOX_ohdr 0x6f686472U
#define BOX_pagt 0x70616774U
#define BOX_pcol 0x70636f6cU
#define BOX_phdr 0x70686472U
#define BOX_scal 0x7363616cU
//  BMFF, QuickTime, MP4, ...:
#define BOX_cinf 0x63696e66U
#define BOX_clip 0x636c6970U
#define BOX_dinf 0x64696e66U
#define BOX_dref 0x64726566U
#define BOX_edts 0x65647473U
//#define BOX_extr 0x65787472U // Irregular format?
#define BOX_fdsa 0x66647361U
#define BOX_fiin 0x6669696eU
#define BOX_free 0x66726565U
#define BOX_hdlr 0x68646c72U
#define BOX_hinf 0x68696e66U
#define BOX_hmhd 0x686d6864U
#define BOX_hnti 0x686e7469U
#define BOX_matt 0x6d617474U
#define BOX_mdia 0x6d646961U
#define BOX_meco 0x6d65636fU
#define BOX_meta 0x6d657461U
#define BOX_minf 0x6d696e66U
#define BOX_mfra 0x6d667261U
#define BOX_moof 0x6d6f6f66U
#define BOX_moov 0x6d6f6f76U
#define BOX_mvex 0x6d766578U
#define BOX_nmhd 0x6e6d6864U
#define BOX_paen 0x7061656eU
#define BOX_rinf 0x72696e66U
#define BOX_schi 0x73636869U
#define BOX_sinf 0x73696e66U
#define BOX_skip 0x736b6970U
#define BOX_smhd 0x736d6864U
#define BOX_stbl 0x7374626cU
#define BOX_stco 0x7374636fU
#define BOX_strd 0x73747264U
#define BOX_strk 0x7374726bU
#define BOX_stsc 0x73747363U
#define BOX_stss 0x73747373U
#define BOX_stsz 0x7374737aU
#define BOX_stts 0x73747473U
#define BOX_stz2 0x73747a32U
#define BOX_traf 0x74726166U
#define BOX_trak 0x7472616bU
#define BOX_tref 0x74726566U
#define BOX_udta 0x75647461U
#define BOX_vmhd 0x766d6864U
// JPEG XT
#define BOX_LCHK 0x4c43484bU
#define BOX_RESI 0x52455349U
#define BOX_SPEC 0x53504543U

#define CODE_Exif 0x45786966U
#define CODE_rICC 0x72494343U
#define CODE_prof 0x70726f66U

static const u8 *g_uuid_cr3_85c0 = (const u8*)"\x85\xc0\xb6\x87\x82\x0f\x11\xe0\x81\x11\xf4\xce\x46\x2b\x6a\x48";
static const u8 *g_uuid_cr3_eaf4 = (const u8*)"\xea\xf4\x2b\x5e\x1c\x98\x4b\x88\xb9\xfb\xb7\xdc\x40\x6e\x4d\x16";

// Called for each primary or compatible brand.
// Brand-specific setup can be done here.
static void apply_brand(deark *c, lctx *d, u32 brand_id)
{
        switch(brand_id) {
        case BRAND_jp2:
                d->is_jp2_jpx_jpm = 1;
                break;
        case BRAND_jpx:
                d->is_jpx = 1;
                d->is_jp2_jpx_jpm = 1;
                break;
        case BRAND_jpm:
                d->is_jpm = 1;
                d->is_jp2_jpx_jpm = 1;
                break;
        case BRAND_mjp2:
        case BRAND_mj2s:
                d->is_bmff = 1;
                d->is_mj2 = 1;
                break;
        case BRAND_isom:
        case BRAND_mp41:
        case BRAND_mp42:
        case BRAND_M4A:
        case BRAND_qt:
                d->is_bmff = 1;
                break;
        case BRAND_mif1:
        case BRAND_heic:
                d->is_heif = 1;
                break;
        default:
                if((brand_id>>16) == 0x3367) { // "3g??"
                        d->is_bmff = 1;
                }
        }
}

// JPEG 2000 signature box (presumably)
static void do_box_jP(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        u32 n;
        struct de_boxdata *curbox = bctx->curbox;

        if(curbox->level!=0) return;
        if(curbox->payload_len<4) return;
        n = (u32)dbuf_getu32be(bctx->f, curbox->payload_pos);
        if(n==0x0d0a870a) {
                de_dbg(c, "found JPEG 2000 signature");
        }
}

static void do_box_ftyp(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        i64 i;
        i64 mver;
        i64 num_compat_brands;
        struct de_fourcc brand4cc;
        struct de_boxdata *curbox = bctx->curbox;

        if(curbox->payload_len<4) goto done;
        dbuf_read_fourcc(bctx->f, curbox->payload_pos, &brand4cc, 4, 0x0);
        d->major_brand = brand4cc.id;
        de_dbg(c, "major brand: '%s'", brand4cc.id_dbgstr);
        if(curbox->level==0)
                apply_brand(c, d, d->major_brand);

        if(curbox->payload_len<8) goto done;
        mver = dbuf_getu32be(bctx->f, curbox->payload_pos+4);
        de_dbg(c, "minor version: %u", (unsigned int)mver);

        if(curbox->payload_len<12) goto done;
        num_compat_brands = (curbox->payload_len - 8)/4;

        for(i=0; i<num_compat_brands; i++) {
                dbuf_read_fourcc(bctx->f, curbox->payload_pos + 8 + i*4, &brand4cc, 4, 0x0);
                if(brand4cc.id==0) continue; // Placeholder. Ignore.
                de_dbg(c, "compatible brand: '%s'", brand4cc.id_dbgstr);
                if(curbox->level==0)
                        apply_brand(c, d, brand4cc.id);
        }

done:
        ;
}

static void do_read_version_and_flags(deark *c, lctx *d, struct de_boxesctx *bctx,
        u8 *version, u32 *flags, int dbgflag)
{
        u8 version1;
        u32 flags1;
        u32 n;
        struct de_boxdata *curbox = bctx->curbox;

        n = (u32)dbuf_getu32be(bctx->f, curbox->payload_pos);
        version1 = (u8)(n>>24);
        flags1 = n&0x00ffffff;
        if(dbgflag) {
                de_dbg(c, "version=%d, flags=0x%06x", (int)version1, (unsigned int)flags1);
        }
        if(version) *version = version1;
        if(flags) *flags = flags1;
}

// For any box whose entire contents are a UTF-8 text string.
static void do_box_justtext(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        struct de_boxdata *curbox = bctx->curbox;
        de_ucstring *s = NULL;
        const char *name;

        name = curbox->box_name ? curbox->box_name : "value";
        s = ucstring_create(c);
        dbuf_read_to_ucstring_n(bctx->f, curbox->payload_pos, curbox->payload_len,
                DE_DBG_MAX_STRLEN, s, 0, DE_ENCODING_UTF8);
        de_dbg(c, "%s: \"%s\"", name, ucstring_getpsz_d(s));
        ucstring_destroy(s);
}

static const char *get_ilst_type_name(unsigned int ns, unsigned int wkt)
{
        const char *name = NULL;

        if(ns!=0) goto done;

        switch(wkt) {
        case 0: name="binary"; break;
        case 1: name="UTF-8"; break;
        case 2: name="UTF-16"; break;
        case 3: name="S/JIS"; break;
        case 4: name="UTF-8 sort key"; break;
        case 5: name="UTF-16 sort key"; break;
        case 13: name="JPEG"; break;
        case 14: name="PNG"; break;
        case 21: name="signed int"; break;
        case 22: name="unsigned int"; break;
        case 23: name="float32"; break;
        case 24: name="float64"; break;
        case 27: name="BMP"; break;
        case 28: name="metadata atom"; break;
        }
done:
        if(!name) name="?";
        return name;
}

static void do_box_data(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        unsigned int type_field, type_namespace, wkt;
        unsigned int cntry, lang;
        i64 vlen;
        struct de_boxdata *curbox = bctx->curbox;
        struct de_boxdata *par;
        struct de_boxdata *gpar;
        i64 pos = curbox->payload_pos;
        de_ucstring *s = NULL;

        par = curbox->parent;
        if(!par) goto done;
        gpar = par->parent;
        if(!gpar) goto done;
        if(gpar->boxtype != BOX_ilst) goto done;

        if(curbox->payload_len<8) goto done;
        type_field = (unsigned int)dbuf_getu32be_p(bctx->f, &pos);
        type_namespace = type_field>>24;
        wkt = (type_field & 0x00ffffff); // well-known type (if namespace==0)
        de_dbg(c, "type: %u, %u (%s)", type_namespace, wkt,
                get_ilst_type_name(type_namespace, wkt));

        cntry = (unsigned int)dbuf_getu16be_p(bctx->f, &pos);
        lang = (unsigned int)dbuf_getu16be_p(bctx->f, &pos);
        de_dbg(c, "locale: %u, %u", cntry, lang);

        if(type_namespace!=0) goto done;
        vlen = curbox->payload_pos + curbox->payload_len - pos;

        if(wkt==1 || wkt==4) { // UTF-8
                s = ucstring_create(c);
                dbuf_read_to_ucstring_n(bctx->f, pos, vlen,
                        DE_DBG_MAX_STRLEN, s, 0, DE_ENCODING_UTF8);
                de_dbg(c, "value: \"%s\"", ucstring_getpsz_d(s));
        }
        else if(wkt==21 && vlen==1) { // 1-byte signed int
                int n;
                n = (int)(signed char)dbuf_getbyte(bctx->f, pos);
                de_dbg(c, "value: %d", n);
        }
        else if(wkt==21 && vlen==2) { // 2-byte BE signed int
                int n;
                n = (int)dbuf_geti16be(bctx->f, pos);
                de_dbg(c, "value: %d", n);
        }
        else if(wkt==0) {
                de_dbg_hexdump(c, bctx->f, pos, vlen, 256, "value", 0x1);
        }
        // TODO: There are lots more types

done:
        ucstring_destroy(s);
}

static void do_box_hdlr(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        de_ucstring *s = NULL;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;
        struct de_fourcc tmp4cc;

        if(curbox->payload_len<4) goto done;
        do_read_version_and_flags(c, d, bctx, NULL, NULL, 1);
        pos += 4;
        if(curbox->payload_len<24) goto done;
        pos += 4; // "Predefined"

        dbuf_read_fourcc(bctx->f, pos, &tmp4cc, 4, 0x0);
        de_dbg(c, "handler type: '%s'", tmp4cc.id_dbgstr);
        pos += 4;

        pos += 12; // reserved
        if(curbox->payload_len<25) goto done;
        if(dbuf_getbyte(bctx->f, pos) == 0x00) goto done;

        s = ucstring_create(c);
        dbuf_read_to_ucstring_n(bctx->f, pos, curbox->payload_pos + curbox->payload_len - pos,
                DE_DBG_MAX_STRLEN, s, DE_CONVFLAG_STOP_AT_NUL, DE_ENCODING_UTF8);
        de_dbg(c, "metadata type name: \"%s\"", ucstring_getpsz_d(s));

done:
        ucstring_destroy(s);
}

static void do_box_tkhd(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        u8 version;
        u32 flags;
        i64 pos;
        double w, h;
        i64 n;
        struct de_boxdata *curbox = bctx->curbox;

        if(curbox->payload_len<4) return;

        pos = curbox->payload_pos;
        do_read_version_and_flags(c, d, bctx, &version, &flags, 1);
        pos+=4;

        if(version==1) {
                if(curbox->payload_len<96) return;
        }
        else {
                if(curbox->payload_len<84) return;
        }

        // creation time, mod time
        if(version==1)
                pos += 8 + 8;
        else
                pos += 4 + 4;

        n = dbuf_getu32be_p(bctx->f, &pos);
        de_dbg(c, "track id: %d", (int)n);

        pos += 4; // reserved

        // duration
        if(version==1)
                pos += 8;
        else
                pos += 4;

        pos += 4*2; // reserved
        pos += 2; // layer
        pos += 2; // alternate group

        n = dbuf_getu16be_p(bctx->f, &pos);
        de_dbg(c, "volume: %.3f", ((double)n)/256.0);

        pos += 2; // reserved
        pos += 4*9; // matrix

        w = dbuf_fmtutil_read_fixed_16_16(bctx->f, pos);
        pos += 4;
        h = dbuf_fmtutil_read_fixed_16_16(bctx->f, pos);
        pos += 4;
        de_dbg(c, "dimensions: %.1f"DE_CHAR_TIMES"%.1f", w, h);
}

static void do_box_vmhd(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        u8 version;
        u32 flags;
        size_t k;
        unsigned int clr[3];
        unsigned int graphicsmode;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;

        if(curbox->payload_len<12) return;
        do_read_version_and_flags(c, d, bctx, &version, &flags, 1);
        pos += 4;
        if(version!=0 || flags!=0x1) return;

        graphicsmode = (unsigned int)dbuf_getu16be_p(bctx->f, &pos);
        de_dbg(c, "graphicsmode: %u", graphicsmode);

        for(k=0; k<3; k++) {
                clr[k] = (unsigned int)dbuf_getu16be_p(bctx->f, &pos);
        }
        de_dbg(c, "opcolor: (%d,%d,%d)", (int)clr[0], (int)clr[1], (int)clr[2]);
}

static void do_box_PICT(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        struct de_boxdata *curbox = bctx->curbox;
        dbuf *outf = NULL;

        outf = dbuf_create_output_file(c, "pict", NULL, DE_CREATEFLAG_IS_AUX);
        dbuf_write_zeroes(outf, 512);
        dbuf_copy(bctx->f, curbox->payload_pos, curbox->payload_len, outf);
        dbuf_close(outf);
}

static void do_box_smhd(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        u8 version;
        u32 flags;
        unsigned int n;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;

        if(curbox->payload_len<8) return;
        do_read_version_and_flags(c, d, bctx, &version, &flags, 1);
        pos += 4;
        if(version!=0 || flags!=0x0) return;

        n = (unsigned int)dbuf_getu16be_p(bctx->f, &pos);
        de_dbg(c, "balance: %u", n);
}

static void do_box_mvhd(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        u8 version;
        u32 flags;
        i64 pos;
        i64 n;
        i64 timescale;
        double nd;
        struct de_boxdata *curbox = bctx->curbox;

        if(curbox->payload_len<4) return;

        pos = curbox->payload_pos;
        do_read_version_and_flags(c, d, bctx, &version, &flags, 1);
        pos+=4;

        if(version==1) {
                if(curbox->payload_len<112) return;
        }
        else {
                if(curbox->payload_len<100) return;
        }

        // creation time, mod time
        if(version==1)
                pos += 8 + 8;
        else
                pos += 4 + 4;

        timescale = dbuf_getu32be_p(bctx->f, &pos);
        de_dbg(c, "timescale: %d time units per second", (int)timescale);

        // duration
        if(version==1) {
                n = dbuf_geti64be(bctx->f, pos);
                pos += 8;
        }
        else {
                n = dbuf_getu32be_p(bctx->f, &pos);
        }
        if(timescale>0)
                nd = (double)n / (double)timescale;
        else
                nd = 0.0;
        de_dbg(c, "duration: %d time units (%.2f seconds)", (int)n, nd);

        nd = dbuf_fmtutil_read_fixed_16_16(bctx->f, pos);
        pos += 4; // rate
        de_dbg(c, "rate: %.3f", nd);

        n = dbuf_getu16be_p(bctx->f, &pos);
        de_dbg(c, "volume: %.3f", ((double)n)/256.0);

        pos += 2; // reserved
        pos += 4*2; // reserved
        pos += 4*9; // matrix
        pos += 4*6; // pre_defined

        n = dbuf_getu32be(bctx->f, pos);
        de_dbg(c, "next track id: %d", (int)n);
}

static void do_box_mdhd(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        u8 version;
        u32 flags;
        i64 pos;
        i64 n;
        i64 timescale;
        double nd;
        struct de_boxdata *curbox = bctx->curbox;

        // TODO: Share code with do_box_mvhd()?
        if(curbox->payload_len<4) return;

        pos = curbox->payload_pos;
        do_read_version_and_flags(c, d, bctx, &version, &flags, 1);
        pos+=4;

        if(version==1) {
                if(curbox->payload_len<36) return;
        }
        else {
                if(curbox->payload_len<24) return;
        }

        // creation time, mod time
        if(version==1)
                pos += 8 + 8;
        else
                pos += 4 + 4;

        timescale = dbuf_getu32be_p(bctx->f, &pos);
        de_dbg(c, "timescale: %d time units per second", (int)timescale);

        // duration
        if(version==1) {
                n = dbuf_geti64be(bctx->f, pos);
                pos += 8;
        }
        else {
                n = dbuf_getu32be_p(bctx->f, &pos);
        }
        if(timescale>0)
                nd = (double)n / (double)timescale;
        else
                nd = 0.0;
        de_dbg(c, "duration: %d time units (%.2f seconds)", (int)n, nd);
}

static void do_box_stsc(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        u8 version;
        u32 flags;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;
        i64 e_count, e_to_print;
        i64 bytesleft;
        i64 k;

        do_read_version_and_flags(c, d, bctx, &version, &flags, 1);
        pos += 4;
        if(version!=0 || flags!=0) return;

        e_count = dbuf_getu32be_p(bctx->f, &pos);
        de_dbg(c, "entry count: %u", (unsigned int)e_count);

        bytesleft = curbox->payload_pos + curbox->payload_len - pos;
        if(bytesleft/12 < e_count) return;

        e_to_print = de_min_int(e_count, d->max_entries_to_print);

        for(k=0; k<e_to_print; k++) {
                i64 first_chunk, spc, sdi;
                first_chunk = dbuf_getu32be_p(bctx->f, &pos);
                spc = dbuf_getu32be_p(bctx->f, &pos);
                sdi = dbuf_getu32be_p(bctx->f, &pos);
                de_dbg(c, "entry[%d]: first chunk=%d, samples/chunk=%d, descr. index=%d",
                        (int)k, (int)first_chunk, (int)spc, (int)sdi);
        }
        if(e_to_print < e_count) {
                de_dbg(c, "[%d more entry(s) omitted, starting at %"I64_FMT"]",
                        (int)(e_count-e_to_print), pos);
        }
}

static void do_box_stsd(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        u8 version;
        u32 flags;
        i64 pos;
        i64 num_entries;
        i64 entry_size;
        struct de_fourcc fmt4cc;
        struct de_boxdata *curbox = bctx->curbox;

        if(curbox->payload_len<8) return;

        pos = curbox->payload_pos;
        do_read_version_and_flags(c, d, bctx, &version, &flags, 1);
        pos += 4;
        if(version!=0) return;

        num_entries = dbuf_getu32be_p(bctx->f, &pos);
        de_dbg(c, "number of sample description entries: %d", (int)num_entries);

        while(1) {
                if(pos + 16 >= curbox->payload_pos + curbox->payload_len) break;
                entry_size = dbuf_getu32be(bctx->f, pos);
                de_dbg(c, "sample description entry at %d, len=%d", (int)pos, (int)entry_size);
                if(entry_size<16) break;

                de_dbg_indent(c, 1);
                dbuf_read_fourcc(bctx->f, pos+4, &fmt4cc, 4, 0x0);
                de_dbg(c, "data format: '%s'", fmt4cc.id_dbgstr);
                de_dbg_indent(c, -1);

                pos += entry_size;
        }
}

// Decode a table of (4- or 8-byte) integers.
// Limit to d->max_entries_to_print.
static void do_simple_int_table(deark *c, lctx *d, struct de_boxesctx *bctx,
        i64 pos1, i64 e_count, i64 e_size,
        const char *s1, const char *s2)
{
        i64 bytesleft;
        i64 e_to_print;
        i64 k;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = pos1;

        if(e_count<=0) return;
        bytesleft = curbox->payload_pos + curbox->payload_len - pos;
        if(bytesleft < e_size*e_count) return;

        e_to_print = de_min_int(e_count, d->max_entries_to_print);

        for(k=0; k<e_to_print; k++) {
                i64 n;

                if(e_size==8) {
                        n = dbuf_geti64be(bctx->f, pos); pos += 8;
                }
                else {
                        n = dbuf_getu32be_p(bctx->f, &pos);
                }

                de_dbg(c, "%s[%"I64_FMT"]: %s=%"I64_FMT, s1, k, s2, n);
        }
        if(e_to_print < e_count) {
                de_dbg(c, "[%"I64_FMT" more %s(s) omitted, starting at %"I64_FMT"]",
                        e_count-e_to_print, s1, pos);
        }
}

static void do_box_stsz(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        u8 version;
        u32 flags;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;
        i64 s_size, s_count;

        do_read_version_and_flags(c, d, bctx, &version, &flags, 1);
        pos += 4;
        if(version!=0 || flags!=0) return;

        s_size = dbuf_getu32be_p(bctx->f, &pos);
        de_dbg(c, "sample size: %u", (unsigned int)s_size);
        s_count = dbuf_getu32be_p(bctx->f, &pos);
        de_dbg(c, "sample count: %u", (unsigned int)s_count);

        if(s_size!=0) goto done;

        do_simple_int_table(c, d, bctx, pos, s_count, 4, "sample", "entry size");

done:
        ;
}

// stco and co64
static void do_box_stco(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        u8 version;
        u32 flags;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;
        i64 e_count;
        i64 e_size;

        do_read_version_and_flags(c, d, bctx, &version, &flags, 1);
        pos += 4;
        if(version!=0 || flags!=0) return;

        e_size = (bctx->curbox->boxtype == BOX_co64) ? 8 : 4;
        e_count = dbuf_getu32be_p(bctx->f, &pos);
        de_dbg(c, "entry count: %u", (unsigned int)e_count);

        do_simple_int_table(c, d, bctx, pos, e_count, e_size, "entry", "chunk offset");
}

static void do_box_stss(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        u8 version;
        u32 flags;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;
        i64 e_count;

        do_read_version_and_flags(c, d, bctx, &version, &flags, 1);
        pos += 4;
        if(version!=0 || flags!=0) return;

        e_count = dbuf_getu32be_p(bctx->f, &pos);
        de_dbg(c, "entry count: %u", (unsigned int)e_count);

        do_simple_int_table(c, d, bctx, pos, e_count, 4, "entry", "sample number");
}

static void do_box_stts(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        u8 version;
        u32 flags;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;
        i64 e_count, e_to_print;
        i64 bytesleft;
        i64 k;

        do_read_version_and_flags(c, d, bctx, &version, &flags, 1);
        pos += 4;
        if(version!=0 || flags!=0) return;

        e_count = dbuf_getu32be_p(bctx->f, &pos);
        de_dbg(c, "entry count: %u", (unsigned int)e_count);

        bytesleft = curbox->payload_pos + curbox->payload_len - pos;
        if(bytesleft/8 < e_count) return;

        e_to_print = de_min_int(e_count, d->max_entries_to_print);

        for(k=0; k<e_to_print; k++) {
                i64 s_count, s_delta;
                s_count = dbuf_getu32be_p(bctx->f, &pos);
                s_delta = dbuf_getu32be_p(bctx->f, &pos);
                de_dbg(c, "entry[%d]: sample count=%d, delta=%d", (int)k,
                        (int)s_count, (int)s_delta);
        }
        if(e_to_print < e_count) {
                de_dbg(c, "[%d more entry(s) omitted, starting at %"I64_FMT"]",
                        (int)(e_count-e_to_print), pos);
        }
}

static void do_box_ctts(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        u8 version;
        u32 flags;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;
        i64 e_count, e_to_print;
        i64 bytesleft;
        i64 k;

        do_read_version_and_flags(c, d, bctx, &version, &flags, 1);
        pos += 4;
        if(version>1 || flags!=0) return;

        e_count = dbuf_getu32be_p(bctx->f, &pos);
        de_dbg(c, "entry count: %u", (unsigned int)e_count);

        bytesleft = curbox->payload_pos + curbox->payload_len - pos;
        if(bytesleft < e_count*8) return;

        e_to_print = e_count;
        if(e_to_print > d->max_entries_to_print) {
                e_to_print = d->max_entries_to_print;
        }

        for(k=0; k<e_to_print; k++) {
                i64 s_count, s_offset;
                s_count = dbuf_getu32be_p(bctx->f, &pos);
                if(version==0) {
                        s_offset = dbuf_getu32be_p(bctx->f, &pos);
                }
                else {
                        s_offset = dbuf_geti32be(bctx->f, pos); pos += 4;
                }
                de_dbg(c, "entry[%d]: sample count=%"I64_FMT", offset=%"I64_FMT,
                        (int)k, s_count, s_offset);
        }
        if(e_to_print < e_count) {
                de_dbg(c, "[%d more entry(s) omitted, starting at %"I64_FMT"]",
                        (int)(e_count-e_to_print), pos);
        }
}

static void do_box_full_superbox(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        struct de_boxdata *curbox = bctx->curbox;

        do_read_version_and_flags(c, d, bctx, NULL, NULL, 1);
        curbox->extra_bytes_before_children = 4;
}

static void do_box_meta(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        if(bctx->curbox->payload_len>=8) {
                // The QuickTime spec says 'meta' is not a full box, but in newer files
                // it is. I don't know how you're supposed to know, but sniffing for
                // "hdlr" should be good enough.
                u32 n = (u32)dbuf_getu32be(bctx->f, bctx->curbox->payload_pos+4);
                if(n==BOX_hdlr) {
                        return;
                }
        }

        do_box_full_superbox(c, d, bctx);
}

static void do_box_jp2c(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        struct de_boxdata *curbox = bctx->curbox;

        de_dbg(c, "JPEG 2000 codestream at %d, len=%d",
                (int)curbox->payload_pos, (int)curbox->payload_len);

        // I think this box is used regardless of the compression format, so make
        // sure it seems to be in "JPEG 2000" format.
        // This is a hack -- we could track the compression method instead.
        if((u32)dbuf_getu32be(bctx->f, curbox->payload_pos) != 0xff4fff51U) {
                de_dbg(c, "[non-J2C]");
                return;
        }

        dbuf_create_file_from_slice(bctx->f, curbox->payload_pos, curbox->payload_len,
                "j2c", NULL, 0);
}

#define POW10_MAX_E 12
static i64 limited_ipow10(int e)
{
        i64 n = 1;

        if(e < 0 || e > POW10_MAX_E) return 1;
        while(e>0) {
                n *= 10;
                e--;
        }
        return n;
}

// TODO: Decide whether to use pow()/libm.
static double limited_pow10(int e)
{
        if(e < -POW10_MAX_E || e > POW10_MAX_E) return 0.0;
        if(e < 0) {
                return 1.0 / (double)limited_ipow10(e);
        }
        return (double)limited_ipow10(e);
}

static void format_jp2_res(char *buf, size_t buflen,
        i64 num, i64 denom, int exponent)
{
        char descr[100];

        if(denom != 0 && exponent >= -POW10_MAX_E && exponent <= POW10_MAX_E) {
                double dpm, dpi;

                dpm = ((double)num / (double)denom) * limited_pow10(exponent);
                dpi = dpm * 0.0254;
                de_snprintf(descr, sizeof(descr),  " = %f points/meter (%f dpi)", dpm, dpi);
        }
        else {
                descr[0] = '\0';
        }
        de_snprintf(buf, buflen, "(%"I64_FMT",%"I64_FMT",%d)%s",
                num, denom, exponent, descr);
}

static void do_box_resc_resd(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        i64 vn, vd, hn, hd;
        int ve, he;
        struct de_boxdata *curbox = bctx->curbox;
        const char *name;
        i64 pos = curbox->payload_pos;
        char res_buf[160];

        if(curbox->boxtype==BOX_resc)
                name = "capture";
        else
                name = "display";

        if(curbox->payload_len<10) return;
        vn = dbuf_getu16be_p(bctx->f, &pos);
        vd = dbuf_getu16be_p(bctx->f, &pos);
        hn = dbuf_getu16be_p(bctx->f, &pos);
        hd = dbuf_getu16be_p(bctx->f, &pos);
        ve = (int)(signed char)dbuf_getbyte_p(bctx->f, &pos);
        he = (int)(signed char)dbuf_getbyte_p(bctx->f, &pos);
        format_jp2_res(res_buf, sizeof(res_buf), vn, vd, ve);
        de_dbg(c, "vert. %s grid res.: %s", name, res_buf);
        format_jp2_res(res_buf, sizeof(res_buf), hn, hd, he);
        de_dbg(c, "horz. %s grid res.: %s", name, res_buf);
}

static const char *get_rreq_sf_name(UI n)
{
        static const u8 ids[11] = {1, 2, 5, 8, 12, 18, 19, 20, 31, 45, 46};
        static const char *names[11] = { "no extensions", "has layers",
                "cmpr=JPEG 2000/15444-1", "no opacity", "contiguous",
                "layers not req'd", "discrete layers", "1 codestream per layer",
                "scaling not req'd", "sRGB", "sRGB-gray" };
        size_t i;

        for(i=0; i<DE_ARRAYCOUNT(ids); i++) {
                if((UI)ids[i]==n) return names[i];
        }
        return "?";
}

static void do_box_rreq(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        i64 pos = bctx->curbox->payload_pos;
        i64 endpos = pos + bctx->curbox->payload_len;
        UI ml;
        i64 nsf, nvf;
        u64 msk;
        i64 i;

        if(pos>=endpos) goto done;
        ml = (UI)dbuf_getbyte_p(bctx->f, &pos);
        de_dbg(c, "ml: %u byte(s)", ml);
        if(ml<1 || ml>8) goto done;

        msk = (u64)dbuf_getint_ext(bctx->f, pos, ml, 0, 0);
        pos += (i64)ml;
        de_dbg(c, "fuam: 0x%"U64_FMTx, msk);

        msk = (u64)dbuf_getint_ext(bctx->f, pos, ml, 0, 0);
        pos += (i64)ml;
        de_dbg(c, "dcm: 0x%"U64_FMTx, msk);

        nsf = dbuf_getu16be_p(bctx->f, &pos);
        de_dbg(c, "nsf: %d", (int)nsf);

        for(i=0; i<nsf; i++) {
                UI sf;

                if(pos>=endpos) goto done;
                sf = (UI)dbuf_getu16be_p(bctx->f, &pos);
                de_dbg(c, "standard feature[%d]: %u (%s)", (int)i, sf, get_rreq_sf_name(sf));

                msk = (u64)dbuf_getint_ext(bctx->f, pos, ml, 0, 0);
                pos += (i64)ml;
                de_dbg_indent(c, 1);
                de_dbg(c, "mask: 0x%"U64_FMTx, msk);
                de_dbg_indent(c, -1);
        }

        if(pos>=endpos) goto done;
        nvf = dbuf_getu16be_p(bctx->f, &pos);
        de_dbg(c, "num. vendor features: %d", (int)nvf);

        for(i=0; i<nvf; i++) {
                u8 ubuf[16];
                char uuid_string[50];

                if(pos>=endpos) goto done;
                dbuf_read(bctx->f, ubuf, pos, 16);
                fmtutil_render_uuid(c, ubuf, uuid_string, sizeof(uuid_string));
                de_dbg(c, "vendor feature[%d]: {%s}", (int)i, uuid_string);
                pos += 16;

                msk = (u64)dbuf_getint_ext(bctx->f, pos, ml, 0, 0);
                pos += (i64)ml;
                de_dbg_indent(c, 1);
                de_dbg(c, "mask: 0x%"U64_FMTx, msk);
                de_dbg_indent(c, -1);
        }

done:
        ;
}

static const char *get_jpeg2000_cmpr_name(deark *c, lctx *d, u8 ct)
{
        const char *name = NULL;

        if(ct==7) { name="JPEG 2000"; goto done; }
        if(d->is_jpx) {
                switch(ct) {
                case 0: name="uncompressed"; break;
                case 1: name="MH"; break;
                case 2: name="MR"; break;
                case 3: name="MMR"; break;
                case 4: name="JBIG bi-level"; break;
                case 5: name="JPEG"; break;
                case 6: name="JPEG-LS"; break;
                case 8: name="JBIG2"; break;
                case 9: name="JBIG"; break;
                }
        }
        // TODO: JPM
done:
        if(!name) name="?";
        return name;
}

static void do_box_ihdr(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        i64 w, h, n;
        u8 b;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;
        char tmps[80];

        if(curbox->payload_len<14) return;
        h = dbuf_getu32be_p(bctx->f, &pos);
        w = dbuf_getu32be_p(bctx->f, &pos);
        de_dbg_dimensions(c, w, h);

        n = dbuf_getu16be_p(bctx->f, &pos);
        de_dbg(c, "number of components: %d", (int)n);

        b = dbuf_getbyte_p(bctx->f, &pos);
        if(b==255) {
                de_strlcpy(tmps, "various", sizeof(tmps));
        }
        else {
                de_snprintf(tmps, sizeof(tmps), "%u bits/comp., %ssigned",
                        (unsigned int)(1+(b&0x7f)), (b&0x80)?"":"un");
        }
        de_dbg(c, "bits-per-component code: %u (%s)", (unsigned int)b, tmps);

        b = dbuf_getbyte_p(bctx->f, &pos);
        de_dbg(c, "compression type: %u (%s)", (unsigned int)b,
                get_jpeg2000_cmpr_name(c, d, b));

        b = dbuf_getbyte_p(bctx->f, &pos);
        de_dbg(c, "colorspace-is-unknown flag: %d", (int)b);
        b = dbuf_getbyte_p(bctx->f, &pos);
        de_dbg(c, "has-IPR: %d", (int)b);
}

static const char *get_channel_type_name(i64 t)
{
        const char *name;
        switch(t) {
        case 0: name = "colour image data for associated color"; break;
        case 1: name = "opacity"; break;
        case 2: name = "premultiplied opacity"; break;
        case 65535: name = "not specified"; break;
        default: name = "?";
        }
        return name;
}

static void do_box_cdef(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        i64 ndescs;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;
        i64 k;

        ndescs = dbuf_getu16be_p(bctx->f, &pos);
        de_dbg(c, "number of channel descriptions: %d", (int)ndescs);

        for(k=0; k<ndescs; k++) {
                i64 idx, typ, asoc;

                if(pos+6 > curbox->payload_pos + curbox->payload_len) break;
                de_dbg(c, "channel description[%d] at %"I64_FMT, (int)k, pos);
                de_dbg_indent(c, 1);
                idx = dbuf_getu16be_p(bctx->f, &pos);
                de_dbg(c, "channel index: %d", (int)idx);
                typ = dbuf_getu16be_p(bctx->f, &pos);
                de_dbg(c, "channel type: %d (%s)", (int)typ, get_channel_type_name(typ));
                asoc = dbuf_getu16be_p(bctx->f, &pos);
                de_dbg(c, "index of associated color: %d", (int)asoc);
                de_dbg_indent(c, -1);
        }
}

// BMFF-style 'colr' box
static void do_box_colr_bmff(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;
        struct de_fourcc ct4cc; // colour_type

        if(curbox->payload_len<4) goto done;

        dbuf_read_fourcc(bctx->f, pos, &ct4cc, 4, 0x0);
        de_dbg(c, "colour type: '%s'", ct4cc.id_dbgstr);
        pos += 4;

        if(ct4cc.id==CODE_rICC || ct4cc.id==CODE_prof) {
                dbuf_create_file_from_slice(bctx->f, pos,
                        curbox->payload_pos+curbox->payload_len-pos,
                        "icc", NULL, DE_CREATEFLAG_IS_AUX);
        }

done:
        ;
}

// JP2/JPX-style 'colr' box
static void do_box_colr_jp2(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        u8 meth;
        u8 n;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;
        const char *s;

        if(curbox->payload_len<3) goto done;
        meth = dbuf_getbyte_p(bctx->f, &pos);
        switch(meth) {
        case 1: s="enumerated"; break;
        case 2: s="ICC profile (restricted)"; break;
        case 3: s="ICC profile (any)"; break; // JPX only
        case 4: s="vendor"; break; // JPX only
        default: s="?";
        }
        de_dbg(c, "specification method: %d (%s)", (int)meth, s);

        n = dbuf_getbyte_p(bctx->f, &pos);
        de_dbg(c, "precedence: %u", (UI)n);
        n = dbuf_getbyte_p(bctx->f, &pos);
        de_dbg(c, "approximation code: %u", (UI)n);

        if(meth==1) {
                unsigned int enumcs;
                if(curbox->payload_len<7) goto done;
                enumcs = (unsigned int)dbuf_getu32be_p(bctx->f, &pos);
                switch(enumcs) {
                        // TODO: There are lots more valid values for JPX.
                case 16: s="sRGB"; break;
                case 17: s="sRGB-like grayscale"; break;
                case 18: s="sYCC"; break;
                default: s="?";
                }
                de_dbg(c, "enumerated colourspace: %u (%s)", enumcs, s);
        }
        else if(meth==2 || meth==3) {
                dbuf_create_file_from_slice(bctx->f,
                        curbox->payload_pos+3, curbox->payload_len-3,
                        "icc", NULL, DE_CREATEFLAG_IS_AUX);
        }

done:
        ;
}

static void do_box_ulst(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;
        i64 nuuids;
        i64 k;
        u8 ubuf[16];
        char uuid_string[50];

        nuuids = dbuf_getu16be_p(bctx->f, &pos);
        de_dbg(c, "number of UUIDs: %d", (int)nuuids);

        for(k=0; k<nuuids; k++) {
                if(pos+16 > curbox->payload_pos + curbox->payload_len) break;
                dbuf_read(bctx->f, ubuf, pos, 16);
                fmtutil_render_uuid(c, ubuf, uuid_string, sizeof(uuid_string));
                de_dbg(c, "UUID[%d]: {%s}", (int)k, uuid_string);
                pos += 16;
        }
}

static void do_box_url(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        de_ucstring *s = NULL;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;
        u32 flags = 0;

        do_read_version_and_flags(c, d, bctx, NULL, &flags, 1);
        pos += 4;

        // "If the self-contained flag is set, [...] no string is present".
        // But there is no flag named "self-contained".
        // I assume it is flag 0x1.
        if(flags&0x000001) goto done;

        s = ucstring_create(c);
        dbuf_read_to_ucstring_n(bctx->f,
                pos, curbox->payload_pos + curbox->payload_len - pos, DE_DBG_MAX_STRLEN,
                s, DE_CONVFLAG_STOP_AT_NUL, DE_ENCODING_UTF8);
        de_dbg(c, "URL: \"%s\"", ucstring_getpsz_d(s));
done:
        ucstring_destroy(s);
}

static void do_box_dtbl(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        i64 ndr;
        struct de_boxdata *curbox = bctx->curbox;

        ndr = dbuf_getu16be(bctx->f, curbox->payload_pos);
        de_dbg(c, "number of data references: %d", (int)ndr);

        curbox->num_children_is_known = 1;
        curbox->num_children = ndr;
        curbox->extra_bytes_before_children = 2;
}

static void do_box_dref(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        i64 nitems;
        u8 version;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;

        do_read_version_and_flags(c, d, bctx, &version, NULL, 1);
        pos += 4;

        nitems = dbuf_getu32be_p(bctx->f, &pos);
        de_dbg(c, "number of items: %u", (unsigned int)nitems);

        curbox->num_children_is_known = 1;
        curbox->num_children = nitems;
        curbox->extra_bytes_before_children = pos - curbox->payload_pos;
}

static void do_box_iinf(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        i64 nitems;
        u8 version;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;

        do_read_version_and_flags(c, d, bctx, &version, NULL, 1);
        pos += 4;

        if(version==0) {
                nitems = dbuf_getu16be_p(bctx->f, &pos);
        }
        else {
                nitems = dbuf_getu32be_p(bctx->f, &pos);
        }
        de_dbg(c, "number of items: %d", (int)nitems);

        curbox->num_children_is_known = 1;
        curbox->num_children = nitems;
        curbox->extra_bytes_before_children = pos - curbox->payload_pos;
}

static void extract_exif_item(deark *c, lctx *d, dbuf *f)
{
        i64 dpos, dlen;
        u8 b0,b1;

        if(!d->exif_item_id_known) return;
        if(d->exif_item_offs<=0) return;
        if(d->exif_item_len<24) return;
        // I'm just guessing the format of this item. It seems to start with 10
        // bytes of header info.
        dpos = d->exif_item_offs+10;
        dlen = d->exif_item_len-10;
        b0 = dbuf_getbyte(f, dpos);
        b1 = dbuf_getbyte(f, dpos+1);
        if(!((b0=='M' && b1=='M') || (b0=='I' && b1=='I'))) {
                return;
        }
        de_dbg(c, "Exif item segment at %"I64_FMT", size=%"I64_FMT, dpos, dlen);
        de_dbg_indent(c, 1);
        fmtutil_handle_exif(c, dpos, dlen);
        de_dbg_indent(c, -1);
}

static void do_box_iloc(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        u8 version;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;
        unsigned int u;
        unsigned int offset_size, length_size, base_offset_size, index_size;
        i64 item_count;
        i64 k;
        int saved_indent_level;

        de_dbg_indent_save(c, &saved_indent_level);
        do_read_version_and_flags(c, d, bctx, &version, NULL, 1);
        pos += 4;

        // TODO: Support more versions
        if(version!=1) goto done;

        u = (unsigned int)dbuf_getbyte_p(bctx->f, &pos);
        offset_size = u>>4;
        de_dbg(c, "offset size: %u", offset_size);
        if(offset_size!=0 && offset_size!=4 && offset_size!=8) goto done;
        length_size = u&0xf;
        de_dbg(c, "length size: %u", length_size);
        if(length_size!=0 && length_size!=4 && length_size!=8) goto done;

        u = (unsigned int)dbuf_getbyte_p(bctx->f, &pos);
        base_offset_size = u>>4;
        de_dbg(c, "base offset size: %u", base_offset_size);
        if(base_offset_size!=0 && base_offset_size!=4 && base_offset_size!=8) goto done;
        index_size =  u&0xf;
        de_dbg(c, "index size: %u", index_size);
        if(index_size!=0 && index_size!=4 && index_size!=8) goto done;

        item_count = dbuf_getu16be_p(bctx->f, &pos);
        de_dbg(c, "item count: %d", (int)item_count);

        for(k=0; k<item_count; k++) {
                unsigned int item_id;
                i64 extent_count;
                i64 e;
                unsigned int cnstr_meth;

                if(pos >= curbox->payload_pos+curbox->payload_len) goto done;
                de_dbg(c, "item[%d] at %"I64_FMT, (int)k, pos);
                de_dbg_indent(c, 1);
                item_id = (unsigned int)dbuf_getu16be_p(bctx->f, &pos);
                de_dbg(c, "item id: %u", item_id);

                u = (unsigned int)dbuf_getu16be_p(bctx->f, &pos);
                cnstr_meth = u&0xf;
                de_dbg(c, "construction method: %u", cnstr_meth);

                pos += 2; // data reference index
                pos += base_offset_size;

                extent_count = dbuf_getu16be_p(bctx->f, &pos);
                de_dbg(c, "extent count: %d", (int)extent_count);

                for(e=0; e<extent_count; e++) {
                        i64 xoffs = 0;
                        i64 xlen = 0;

                        if(pos >= curbox->payload_pos+curbox->payload_len) goto done;
                        de_dbg(c, "extent[%d]", (int)e);
                        de_dbg_indent(c, 1);
                        pos += index_size;

                        if(offset_size>0) {
                                xoffs = dbuf_getint_ext(bctx->f, pos, offset_size, 0, 0);
                                de_dbg(c, "offset: %"I64_FMT, xoffs);
                        }
                        pos += offset_size;

                        if(length_size>0) {
                                xlen = dbuf_getint_ext(bctx->f, pos, length_size, 0, 0);
                                de_dbg(c, "length: %"I64_FMT, xlen);
                        }
                        pos += length_size;

                        if(d->exif_item_id_known && item_id==d->exif_item_id && extent_count==1) {
                                de_dbg(c, "[Exif item]");
                                d->exif_item_offs = xoffs;
                                d->exif_item_len = xlen;
                        }

                        de_dbg_indent(c, -1);
                }

                de_dbg_indent(c, -1);
        }

done:
        if(d->exif_item_id_known) {
                extract_exif_item(c, d, bctx->f);
        }
        de_dbg_indent_restore(c, saved_indent_level);
}

static void do_box_infe(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        u8 version;
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;
        i64 n;
        unsigned int item_id;

        do_read_version_and_flags(c, d, bctx, &version, NULL, 1);
        pos += 4;

        if(version==2 || version==3) {
                struct de_fourcc itemtype4cc;

                if(version==2) {
                        item_id = (unsigned int)dbuf_getu16be_p(bctx->f, &pos);
                }
                else {
                        item_id = (unsigned int)dbuf_getu32be_p(bctx->f, &pos);
                }
                de_dbg(c, "item id: %u", item_id);

                n = dbuf_getu16be_p(bctx->f, &pos);
                de_dbg(c, "item protection: %u", (unsigned int)n);

                dbuf_read_fourcc(bctx->f, pos, &itemtype4cc, 4, 0x0);
                pos += 4;
                de_dbg(c, "item type: '%s'", itemtype4cc.id_dbgstr);

                if(itemtype4cc.id==CODE_Exif) {
                        d->exif_item_id_known = 1;
                        d->exif_item_id = item_id;
                }

                // TODO: string item_name
                // TODO: sometimes there are additional strings after item_name
        }
}

static void do_box_ispe(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        struct de_boxdata *curbox = bctx->curbox;
        i64 pos = curbox->payload_pos;
        i64 w, h;

        if(curbox->payload_len<12) return;
        do_read_version_and_flags(c, d, bctx, NULL, NULL, 1);
        pos += 4;
        w = dbuf_getu32be_p(bctx->f, &pos);
        h = dbuf_getu32be_p(bctx->f, &pos);
        de_dbg_dimensions(c, w, h);
}

static void do_box_xml(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        struct de_boxdata *curbox = bctx->curbox;

        // TODO: Detect the specific XML format, and use it to choose a better
        // filename.
        de_dbg(c, "XML data at %d, len=%d", (int)curbox->payload_pos, (int)curbox->payload_len);
        dbuf_create_file_from_slice(bctx->f, curbox->payload_pos, curbox->payload_len,
                "xml", NULL, DE_CREATEFLAG_IS_AUX);
}

static void do_box_THMB(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        struct de_boxdata *curbox = bctx->curbox;
        i64 img_pos;
        i64 img_len;

        if(!curbox->parent) return;
        if(!curbox->parent->is_uuid) return;
        if(de_memcmp(curbox->parent->uuid, g_uuid_cr3_85c0, 16)) return;
        if(curbox->payload_len<20) return;
        img_pos= curbox->payload_pos+16;
        if(dbuf_memcmp(bctx->f, img_pos, "\xff\xd8\xff", 3)) return;
        img_len = dbuf_getu32be(bctx->f, curbox->payload_pos+8);
        de_dbg(c, "image at %"I64_FMT", len=%"I64_FMT, img_pos, img_len);
        if(img_pos+img_len > curbox->payload_pos+curbox->payload_len) return;
        dbuf_create_file_from_slice(bctx->f, img_pos, img_len, "thumb.jpg", NULL,
                DE_CREATEFLAG_IS_AUX);
}

static void do_box_PRVW(deark *c, lctx *d, struct de_boxesctx *bctx)
{
        struct de_boxdata *curbox = bctx->curbox;
        i64 img_pos;
        i64 img_len;

        if(!curbox->parent) return;
        if(!curbox->parent->is_uuid) return;
        if(de_memcmp(curbox->parent->uuid, g_uuid_cr3_eaf4, 16)) return;
        if(curbox->payload_len<20) return;
        img_pos= curbox->payload_pos+16;
        if(dbuf_memcmp(bctx->f, img_pos, "\xff\xd8\xff", 3)) return;
        img_len = dbuf_getu32be(bctx->f, curbox->payload_pos+12);
        de_dbg(c, "image at %"I64_FMT", len=%"I64_FMT, img_pos, img_len);
        if(img_pos+img_len > curbox->payload_pos+curbox->payload_len) return;
        dbuf_create_file_from_slice(bctx->f, img_pos, img_len, "preview.jpg", NULL,
                DE_CREATEFLAG_IS_AUX);
}

// The first line that matches will be used, so items related to more-specific
// formats/brands should be listed first.
static const struct box_type_info box_type_info_arr[] = {
        {BOX_ftyp, 0x00000000, 0x00000002, "file type", do_box_ftyp},
        {BOX_jP  , 0x00010008, 0x00000002, "JPEG 2000 signature", do_box_jP},
        {BOX_mdat, 0x00000008, 0x00000001, "media data", NULL},
        {BOX_mdat, 0x00080001, 0x00000000, "media data", NULL},
        {BOX_alis, 0x00000001, 0x00000000, "Macintosh file alias", NULL},
        {BOX_cinf, 0x00000001, 0x00000001, "complete track information", NULL},
        {BOX_clip, 0x00000001, 0x00000001, NULL, NULL},
        {BOX_co64, 0x00000001, 0x00000000, "chunk offset", do_box_stco},
        {BOX_colr, 0x00080001, 0x00000000, "colour information", do_box_colr_bmff},
        {BOX_dinf, 0x00080001, 0x00000001, "data information", NULL},
        {BOX_dref, 0x00080001, 0x00000001, "data reference", do_box_dref},
        {BOX_edts, 0x00000001, 0x00000001, "edit", NULL},
        {BOX_elst, 0x00000001, 0x00000000, "edit list", NULL},
        {BOX_fdsa, 0x00000001, 0x00000001, NULL, NULL},
        {BOX_fiin, 0x00000001, 0x00000001, "FD item information", NULL},
        {BOX_free, 0x00090001, 0x00000000, "free space", NULL},
        {BOX_hdlr, 0x00080001, 0x00000000, "handler reference", do_box_hdlr},
        {BOX_hinf, 0x00000001, 0x00000001, NULL, NULL},
        {BOX_hmhd, 0x00000001, 0x00000000, "hint media header", NULL},
        {BOX_hnti, 0x00000001, 0x00000001, NULL, NULL},
        {BOX_iinf, 0x00080001, 0x00000001, "item info", do_box_iinf},
        {BOX_iloc, 0x00080001, 0x00000000, "item location", do_box_iloc},
        {BOX_ilst, 0x00000001, 0x00000001, "metadata item list", NULL},
        {BOX_infe, 0x00080001, 0x00000000, "item info entry", do_box_infe},
        {BOX_iods, 0x00000001, 0x00000000, "object descriptor", NULL},
        {BOX_iref, 0x00080001, 0x00000001, "item reference", do_box_full_superbox},
        {BOX_load, 0x00000001, 0x00000000, "track load settings", NULL},
        {BOX_matt, 0x00000001, 0x00000001, NULL, NULL},
        {BOX_mdhd, 0x00000001, 0x00000000, "media header", do_box_mdhd},
        {BOX_mdia, 0x00000001, 0x00000001, "media", NULL},
        {BOX_meco, 0x00000001, 0x00000001, "additional metadata container", NULL},
        {BOX_meta, 0x00080001, 0x00000001, "metadata", do_box_meta},
        {BOX_minf, 0x00000001, 0x00000001, "media information", NULL},
        {BOX_mfra, 0x00000001, 0x00000001, "movie fragment random access", NULL},
        {BOX_moof, 0x00000001, 0x00000001, "movie fragment", NULL},
        {BOX_moov, 0x00000001, 0x00000001, "movie (metadata container)", NULL},
        {BOX_mvex, 0x00000001, 0x00000001, "movie extends", NULL},
        {BOX_mvhd, 0x00000001, 0x00000000, "movie header", do_box_mvhd},
        {BOX_nmhd, 0x00000001, 0x00000000, "null media header", NULL},
        {BOX_paen, 0x00000001, 0x00000001, NULL, NULL},
        {BOX_pnot, 0x00000001, 0x00000000, "reference to movie preview", NULL},
        {BOX_rinf, 0x00000001, 0x00000001, "restricted scheme information", NULL},
        {BOX_rsrc, 0x00000001, 0x00000000, "Macintosh resource alias", NULL},
        {BOX_sbgp, 0x00000001, 0x00000000, "sample-to-group", NULL},
        {BOX_schi, 0x00000001, 0x00000001, "scheme information", NULL},
        {BOX_sdtp, 0x00000001, 0x00000000, "independent and disposable samples", NULL},
        {BOX_sgpd, 0x00000001, 0x00000000, "sample group description", NULL},
        {BOX_sinf, 0x00000001, 0x00000001, "protection scheme information", NULL},
        {BOX_skip, 0x00080001, 0x00000000, "user-data", NULL},
        {BOX_smhd, 0x00000001, 0x00000000, "sound media header", do_box_smhd},
        {BOX_stbl, 0x00000001, 0x00000001, "sample table", NULL},
        {BOX_stco, 0x00000001, 0x00000000, "chunk offset", do_box_stco},
        {BOX_strd, 0x00000001, 0x00000001, "sub track definition", NULL},
        {BOX_strk, 0x00000001, 0x00000001, "sub track", NULL},
        {BOX_stsc, 0x00000001, 0x00000000, "sample to chunk", do_box_stsc},
        {BOX_stsd, 0x00000001, 0x00000000, "sample description", do_box_stsd},
        {BOX_stss, 0x00000001, 0x00000000, "sync sample", do_box_stss},
        {BOX_stsz, 0x00000001, 0x00000000, "sample sizes", do_box_stsz},
        {BOX_stts, 0x00000001, 0x00000000, "decoding time to sample", do_box_stts},
        {BOX_ctts, 0x00000001, 0x00000000, "composition time to sample", do_box_ctts},
        {BOX_stz2, 0x00000001, 0x00000000, "compact sample size", NULL},
        {BOX_tkhd, 0x00000001, 0x00000000, "track header", do_box_tkhd},
        {BOX_traf, 0x00000001, 0x00000001, "track fragment", NULL},
        {BOX_trak, 0x00000001, 0x00000001, "track", NULL},
        {BOX_tref, 0x00000001, 0x00000001, "track reference", NULL},
        {BOX_udta, 0x00000001, 0x00000001, "user data", NULL},
        {BOX_url , 0x00090001, 0x00000000, "URL", do_box_url},
        {BOX_vmhd, 0x00000001, 0x00000000, "video media header", do_box_vmhd},
        {BOX_wide, 0x00000001, 0x00000000, "reserved space", NULL},
        {BOX_PICT, 0x00000001, 0x00000000, "QuickDraw picture", do_box_PICT},
        {BOX_PRVW, 0x00000001, 0x00000000, "preview", do_box_PRVW},
        {BOX_THMB, 0x00000001, 0x00000000, "thumbnail", do_box_THMB},
        {BOX_asoc, 0x00010000, 0x00000001, "association", NULL},
        {BOX_cgrp, 0x00010000, 0x00000001, "colour group", NULL},
        {BOX_cdef, 0x00010000, 0x00000000, "channel definition", do_box_cdef},
        {BOX_colr, 0x00010000, 0x00000000, "colour specification", do_box_colr_jp2},
        {BOX_comp, 0x00010000, 0x00000001, NULL, NULL},
        {BOX_drep, 0x00010000, 0x00000001, NULL, NULL},
        {BOX_dtbl, 0x00010000, 0x00000001, "data reference", do_box_dtbl},
        {BOX_flst, 0x00010000, 0x00000000, "fragment list", NULL},
        {BOX_ftbl, 0x00010000, 0x00000001, "fragment table", NULL},
        {BOX_ihdr, 0x00010000, 0x00000000, "image header", do_box_ihdr},
        {BOX_jp2c, 0x00010008, 0x00000000, "contiguous codestream", do_box_jp2c},
        {BOX_jp2h, 0x00010000, 0x00000001, "JP2 header", NULL},
        {BOX_jpch, 0x00010000, 0x00000001, "codestream header", NULL},
        {BOX_jplh, 0x00010000, 0x00000001, "compositing layer header", NULL},
        {BOX_lhdr, 0x00010000, 0x00000000, "layout object header", NULL},
        {BOX_lbl , 0x00010000, 0x00000000, "label", do_box_justtext},
        {BOX_lobj, 0x00010000, 0x00000001, "layout object", NULL},
        {BOX_mhdr, 0x00010000, 0x00000000, "compound image header", NULL},
        {BOX_nlst, 0x00010000, 0x00000000, "number list", NULL},
        {BOX_objc, 0x00010000, 0x00000001, "object", NULL},
        {BOX_ohdr, 0x00010000, 0x00000000, "object header", NULL},
        {BOX_page, 0x00010000, 0x00000001, "page", NULL},
        {BOX_pagt, 0x00010000, 0x00000000, "page table", NULL},
        {BOX_pcol, 0x00010000, 0x00000001, "page collection", NULL},
        {BOX_phdr, 0x00010000, 0x00000000, "page header", NULL},
        {BOX_res , 0x00010000, 0x00000001, "resolution", NULL},
        {BOX_resc, 0x00010000, 0x00000000, "capture resolution", do_box_resc_resd},
        {BOX_resd, 0x00010000, 0x00000000, "default display resolution", do_box_resc_resd},
        {BOX_rreq, 0x00010000, 0x00000000, "reader requirements", do_box_rreq},
        {BOX_scal, 0x00010000, 0x00000000, "object scale", NULL},
        {BOX_sdat, 0x00010000, 0x00000001, NULL, NULL},
        {BOX_uinf, 0x00010000, 0x00000001, "UUID info", NULL},
        {BOX_ulst, 0x00010000, 0x00000000, "UUID list", do_box_ulst},
        {BOX_xml , 0x00010008, 0x00000000, "XML", do_box_xml},
        {BOX_LCHK, 0x00040000, 0x00000000, "checksum", NULL},
        {BOX_RESI, 0x00040000, 0x00000000, "residual codestream", NULL},
        {BOX_SPEC, 0x00040000, 0x00000001, NULL, NULL},
        {BOX_auxC, 0x00080000, 0x00000000, "auxiliary type property", NULL},
        {BOX_grpl, 0x00080000, 0x00000000, "groups list", NULL},
        {BOX_idat, 0x00080000, 0x00000000, "item data", NULL},
        {BOX_ipco, 0x00080000, 0x00000001, "item property container", NULL},
        {BOX_ipma, 0x00080000, 0x00000000, "item property association", NULL},
        {BOX_ipro, 0x00080000, 0x00000000, "item protection", NULL},
        {BOX_iprp, 0x00080000, 0x00000001, "item properties", NULL},
        {BOX_ispe, 0x00080000, 0x00000000, "image spatial extents", do_box_ispe},
        {BOX_hvcC, 0x00080000, 0x00000000, "HEVC configuration", NULL},
        {BOX_pitm, 0x00080000, 0x00000000, "primary item", NULL}
};

// TODO: These ilst (iTunes metadata?) boxes should probably go in the above
// list, but the logic for finding the right box will be complicated.
// Superboxes are not flagged in this list, because that determination
// is based on their location, not their type.
static const struct box_type_info ilst_box_type_info_arr[] = {
        {BOX_data,   0x01000000, 0x00000000, "value atom", do_box_data},
        {BOX_name,   0x01000000, 0x00000000, "name atom", NULL},
        {BOX_blank,  0x01000000, 0x00000000, "custom metadata item", NULL},
        {BOX_cpil,   0x01000000, 0x00000000, "compilation", NULL},
        {BOX_gnre,   0x01000000, 0x00000000, "genre (enumerated)", NULL},
        {BOX_tmpo,   0x01000000, 0x00000000, "tempo", NULL},
        {BOX_a9ART,  0x01000000, 0x00000000, "artist", NULL},
        {BOX_a9cmt,  0x01000000, 0x00000000, "comment", NULL},
        {BOX_a9nam,  0x01000000, 0x00000000, "name / title", NULL},
        {BOX_a9too,  0x01000000, 0x00000000, "encoder software", NULL}
};

static const struct box_type_info *find_box_type_info(deark *c, lctx *d,
        u32 boxtype, int level)
{
        size_t k;
        u32 mask = 0;

        if(d->is_bmff) mask |= 0x00000001;
        if(d->is_mj2) mask |= 0x000000008;
        if(d->is_jp2_jpx_jpm) mask |= 0x00010000;
        if(d->is_jpegxt) mask |= 0x00040000;
        if(d->is_heif) mask |= 0x00080000;

        for(k=0; k<DE_ARRAYCOUNT(box_type_info_arr); k++) {
                if(box_type_info_arr[k].boxtype != boxtype) continue;
                if(level==0 && (box_type_info_arr[k].flags2 & 0x2)) {
                        // Critical box. Always match.
                        return &box_type_info_arr[k];
                }
                if((box_type_info_arr[k].flags1 & mask)==0) continue;
                return &box_type_info_arr[k];
        }
        return NULL;
}

static const struct box_type_info *find_ilst_box_type_info(deark *c, lctx *d,
        u32 boxtype)
{
        size_t k;

        for(k=0; k<DE_ARRAYCOUNT(ilst_box_type_info_arr); k++) {
                if(ilst_box_type_info_arr[k].boxtype != boxtype) continue;
                return &ilst_box_type_info_arr[k];
        }
        return NULL;
}

static void my_box_identify_fn(deark *c, struct de_boxesctx *bctx)
{
        const struct box_type_info *bti;
        lctx *d = (lctx*)bctx->userdata;
        struct de_boxdata *curbox = bctx->curbox;
        struct de_boxdata *par = curbox->parent;
        struct de_boxdata *gpar = NULL;
        int is_ilst_child = 0;

        if(curbox->boxtype != BOX_uuid) {
                curbox->box_name = "?";
        }

        if(par) {
                gpar = par->parent;
        }

        if((par && (par->boxtype==BOX_ilst)) ||
                (gpar && (gpar->boxtype==BOX_ilst)) )
        {
                is_ilst_child = 1;
        }

        if(is_ilst_child) {
                bti = find_ilst_box_type_info(c, d, curbox->boxtype);
        }
        else {
                bti = find_box_type_info(c, d, curbox->boxtype, curbox->level);
        }

        if(bti) {
                // So that we don't have to run "find" again in my_box_handler(),
                // record it here.
                curbox->box_userdata = (void*)bti;

                if(bti->name) {
                        curbox->box_name = bti->name;
                }
        }
        // TODO: Do we need special handling of 'data' boxes?
}

static int my_box_handler(deark *c, struct de_boxesctx *bctx)
{
        const struct box_type_info *bti;
        lctx *d = (lctx*)bctx->userdata;
        struct de_boxdata *curbox = bctx->curbox;

        if(curbox->is_uuid) {
                if(!de_memcmp(curbox->uuid, g_uuid_cr3_85c0, 16)) {
                        curbox->is_superbox = 1;
                }
                else if(!de_memcmp(curbox->uuid, g_uuid_cr3_eaf4, 16)) {
                        curbox->is_superbox = 1;
                        curbox->extra_bytes_before_children = 8;
                }
                else {
                        return fmtutil_default_box_handler(c, bctx);
                }
                return 1;
        }

        bti = (const struct box_type_info *)curbox->box_userdata;

        if(bti && (bti->flags2 & 0x1)) {
                curbox->is_superbox = 1;
        }
        else if(d->is_bmff && curbox->parent && (curbox->parent->boxtype==BOX_ilst)) {
                curbox->is_superbox = 1;
        }

        if(bti && bti->hfn) {
                bti->hfn(c, d, bctx);
        }

        return 1;
}

static void de_run_bmff(deark *c, de_module_params *mparams)
{
        lctx *d = NULL;
        struct de_boxesctx *bctx = NULL;
        int skip_autodetect = 0;
        const char *s;

        d = de_malloc(c, sizeof(lctx));
        bctx = de_malloc(c, sizeof(struct de_boxesctx));

        if(de_havemodcode(c, mparams, 'T')) {
                d->is_jpegxt = 1;
                skip_autodetect = 1;
        }
        if(de_havemodcode(c, mparams, 'X')) {
                d->is_jpx = 1;
                d->is_jp2_jpx_jpm = 1;
                skip_autodetect = 1;
        }
        if(de_havemodcode(c, mparams, 'B')) {
                d->is_bmff = 1;
                skip_autodetect = 1;
        }

        if(!skip_autodetect) {
                u32 first_boxtype;
                // Try to detect old QuickTime files that don't have an ftyp box.
                first_boxtype = (u32)de_getu32be(4);
                if(first_boxtype==BOX_mdat || first_boxtype==BOX_moov ||
                        first_boxtype==BOX_free || first_boxtype==BOX_wide ||
                        first_boxtype==BOX_skip || first_boxtype==BOX_pnot)
                {
                        d->is_bmff = 1;
                }
        }

        s = de_get_ext_option(c, "bmff:maxentries");
        if(s) {
                d->max_entries_to_print = de_atoi64(s);
        }
        else {
                d->max_entries_to_print = 32;
        }
        if(d->max_entries_to_print<0) {
                d->max_entries_to_print = 0;
        }

        bctx->userdata = (void*)d;
        bctx->f = c->infile;
        bctx->identify_box_fn = my_box_identify_fn;
        bctx->handle_box_fn = my_box_handler;

        fmtutil_read_boxes_format(c, bctx);

        de_free(c, bctx);
        de_free(c, d);
}

static int de_identify_jpeg2000(deark *c)
{
        if(!dbuf_memcmp(c->infile, 0, "\x00\x00\x00\x0c\x6a\x50\x20\x20\x0d\x0a\x87\x0a", 12))
                return 100;
        return 0;
}

static void de_help_bmff(deark *c)
{
        de_msg(c, "-opt bmff:maxentries=<n> : Number of sample table entries to print with -d");
}

void de_module_jpeg2000(deark *c, struct deark_module_info *mi)
{
        mi->id = "jpeg2000";
        mi->desc = "JPEG 2000 image";
        mi->desc2 = "resources only";
        mi->run_fn = de_run_bmff;
        mi->identify_fn = de_identify_jpeg2000;
}

static int de_identify_bmff(deark *c)
{
        u32 first_boxtype;

        first_boxtype = (u32)de_getu32be(4);
        if(first_boxtype==BOX_ftyp) return 80;
        if(first_boxtype==BOX_mdat) return 35;
        if(first_boxtype==BOX_moov) return 35;
        if(first_boxtype==BOX_skip) return 10;
        if(first_boxtype==BOX_wide) return 10;
        if(first_boxtype==BOX_pnot) return 10;
        if(first_boxtype==BOX_free) return 9;
        return 0;
}

void de_module_bmff(deark *c, struct deark_module_info *mi)
{
        mi->id = "bmff";
        mi->desc = "ISO Base Media File Format";
        mi->desc2 = "MP4, QuickTime, etc.";
        mi->id_alias[0] = "mp4";
        mi->run_fn = de_run_bmff;
        mi->identify_fn = de_identify_bmff;
        mi->help_fn = de_help_bmff;
}