libavcodec/8bps.c

   1 /*
   2  * Quicktime Planar RGB (8BPS) Video Decoder
   3  * Copyright (C) 2003 Roberto Togni
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * Libav is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with Libav; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file
  24  * QT 8BPS Video Decoder by Roberto Togni
  25  * For more information about the 8BPS format, visit:
  26  *   http://www.pcisys.net/~melanson/codecs/
  27  *
  28  * Supports: PAL8 (RGB 8bpp, paletted)
  29  *         : BGR24 (RGB 24bpp) (can also output it as RGB32)
  30  *         : RGB32 (RGB 32bpp, 4th plane is probably alpha and it's ignored)
  31  *
  32  */
  33
  34 #include <stdio.h>
  35 #include <stdlib.h>
  36 #include <string.h>
  37
  38 #include "libavutil/internal.h"
  39 #include "libavutil/intreadwrite.h"
  40 #include "avcodec.h"
  41 #include "internal.h"
  42
  43
  44 static const enum AVPixelFormat pixfmt_rgb24[] = {
  45     AV_PIX_FMT_BGR24, AV_PIX_FMT_RGB32, AV_PIX_FMT_NONE };
  46
  47 typedef struct EightBpsContext {
  48     AVCodecContext *avctx;
  49
  50     unsigned char planes;
  51     unsigned char planemap[4];
  52
  53     uint32_t pal[256];
  54 } EightBpsContext;
  55
  56 static int decode_frame(AVCodecContext *avctx, void *data,
  57                         int *got_frame, AVPacket *avpkt)
  58 {
  59     AVFrame *frame = data;
  60     const uint8_t *buf = avpkt->data;
  61     int buf_size       = avpkt->size;
  62     EightBpsContext * const c = avctx->priv_data;
  63     const unsigned char *encoded = buf;
  64     unsigned char *pixptr, *pixptr_end;
  65     unsigned int height = avctx->height; // Real image height
  66     unsigned int dlen, p, row;
  67     const unsigned char *lp, *dp;
  68     unsigned char count;
  69     unsigned int px_inc;
  70     unsigned int planes     = c->planes;
  71     unsigned char *planemap = c->planemap;
  72     int ret;
  73
  74     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
  75         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
  76         return ret;
  77     }
  78
  79     /* Set data pointer after line lengths */
  80     dp = encoded + planes * (height << 1);
  81
  82     /* Ignore alpha plane, don't know what to do with it */
  83     if (planes == 4)
  84         planes--;
  85
  86     px_inc = planes + (avctx->pix_fmt == AV_PIX_FMT_RGB32);
  87
  88     for (p = 0; p < planes; p++) {
  89         /* Lines length pointer for this plane */
  90         lp = encoded + p * (height << 1);
  91
  92         /* Decode a plane */
  93         for (row = 0; row < height; row++) {
  94             pixptr = frame->data[0] + row * frame->linesize[0] + planemap[p];
  95             pixptr_end = pixptr + frame->linesize[0];
  96             dlen = av_be2ne16(*(const unsigned short *)(lp + row * 2));
  97             /* Decode a row of this plane */
  98             while (dlen > 0) {
  99                 if (dp + 1 >= buf + buf_size)
 100                     return AVERROR_INVALIDDATA;
 101                 if ((count = *dp++) <= 127) {
 102                     count++;
 103                     dlen -= count + 1;
 104                     if (pixptr + count * px_inc > pixptr_end)
 105                         break;
 106                     if (dp + count > buf + buf_size)
 107                         return AVERROR_INVALIDDATA;
 108                     while (count--) {
 109                         *pixptr = *dp++;
 110                         pixptr += px_inc;
 111                     }
 112                 } else {
 113                     count = 257 - count;
 114                     if (pixptr + count * px_inc > pixptr_end)
 115                         break;
 116                     while (count--) {
 117                         *pixptr = *dp;
 118                         pixptr += px_inc;
 119                     }
 120                     dp++;
 121                     dlen -= 2;
 122                 }
 123             }
 124         }
 125     }
 126
 127     if (avctx->bits_per_coded_sample <= 8) {
 128         const uint8_t *pal = av_packet_get_side_data(avpkt,
 129                                                      AV_PKT_DATA_PALETTE,
 130                                                      NULL);
 131         if (pal) {
 132             frame->palette_has_changed = 1;
 133             memcpy(c->pal, pal, AVPALETTE_SIZE);
 134         }
 135
 136         memcpy (frame->data[1], c->pal, AVPALETTE_SIZE);
 137     }
 138
 139     *got_frame = 1;
 140
 141     /* always report that the buffer was completely consumed */
 142     return buf_size;
 143 }
 144
 145 static av_cold int decode_init(AVCodecContext *avctx)
 146 {
 147     EightBpsContext * const c = avctx->priv_data;
 148
 149     c->avctx       = avctx;
 150
 151     switch (avctx->bits_per_coded_sample) {
 152     case 8:
 153         avctx->pix_fmt = AV_PIX_FMT_PAL8;
 154         c->planes      = 1;
 155         c->planemap[0] = 0; // 1st plane is palette indexes
 156         break;
 157     case 24:
 158         avctx->pix_fmt = avctx->get_format(avctx, pixfmt_rgb24);
 159         c->planes      = 3;
 160         c->planemap[0] = 2; // 1st plane is red
 161         c->planemap[1] = 1; // 2nd plane is green
 162         c->planemap[2] = 0; // 3rd plane is blue
 163         break;
 164     case 32:
 165         avctx->pix_fmt = AV_PIX_FMT_RGB32;
 166         c->planes      = 4;
 167 #if HAVE_BIGENDIAN
 168         c->planemap[0] = 1; // 1st plane is red
 169         c->planemap[1] = 2; // 2nd plane is green
 170         c->planemap[2] = 3; // 3rd plane is blue
 171         c->planemap[3] = 0; // 4th plane is alpha???
 172 #else
 173         c->planemap[0] = 2; // 1st plane is red
 174         c->planemap[1] = 1; // 2nd plane is green
 175         c->planemap[2] = 0; // 3rd plane is blue
 176         c->planemap[3] = 3; // 4th plane is alpha???
 177 #endif
 178         break;
 179     default:
 180         av_log(avctx, AV_LOG_ERROR, "Error: Unsupported color depth: %u.\n",
 181                avctx->bits_per_coded_sample);
 182         return AVERROR_INVALIDDATA;
 183     }
 184
 185     return 0;
 186 }
 187
 188 AVCodec ff_eightbps_decoder = {
 189     .name           = "8bps",
 190     .type           = AVMEDIA_TYPE_VIDEO,
 191     .id             = AV_CODEC_ID_8BPS,
 192     .priv_data_size = sizeof(EightBpsContext),
 193     .init           = decode_init,
 194     .decode         = decode_frame,
 195     .capabilities   = CODEC_CAP_DR1,
 196     .long_name      = NULL_IF_CONFIG_SMALL("QuickTime 8BPS video"),
 197 };