libavcodec/loco.c

   1 /*
   2  * LOCO codec
   3  * Copyright (c) 2005 Konstantin Shishkov
   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  * LOCO codec.
  25  */
  26
  27 #include "avcodec.h"
  28 #include "get_bits.h"
  29 #include "golomb.h"
  30 #include "internal.h"
  31 #include "mathops.h"
  32
  33 enum LOCO_MODE {
  34     LOCO_UNKN  =  0,
  35     LOCO_CYUY2 = -1,
  36     LOCO_CRGB  = -2,
  37     LOCO_CRGBA = -3,
  38     LOCO_CYV12 = -4,
  39     LOCO_YUY2  =  1,
  40     LOCO_UYVY  =  2,
  41     LOCO_RGB   =  3,
  42     LOCO_RGBA  =  4,
  43     LOCO_YV12  =  5,
  44 };
  45
  46 typedef struct LOCOContext {
  47     AVCodecContext *avctx;
  48     int lossy;
  49     int mode;
  50 } LOCOContext;
  51
  52 typedef struct RICEContext {
  53     GetBitContext gb;
  54     int save, run, run2; /* internal rice decoder state */
  55     int sum, count; /* sum and count for getting rice parameter */
  56     int lossy;
  57 } RICEContext;
  58
  59 static int loco_get_rice_param(RICEContext *r)
  60 {
  61     int cnt = 0;
  62     int val = r->count;
  63
  64     while (r->sum > val && cnt < 9) {
  65         val <<= 1;
  66         cnt++;
  67     }
  68
  69     return cnt;
  70 }
  71
  72 static inline void loco_update_rice_param(RICEContext *r, int val)
  73 {
  74     r->sum += val;
  75     r->count++;
  76
  77     if (r->count == 16) {
  78         r->sum   >>= 1;
  79         r->count >>= 1;
  80     }
  81 }
  82
  83 static inline int loco_get_rice(RICEContext *r)
  84 {
  85     int v;
  86     if (r->run > 0) { /* we have zero run */
  87         r->run--;
  88         loco_update_rice_param(r, 0);
  89         return 0;
  90     }
  91     v = get_ur_golomb_jpegls(&r->gb, loco_get_rice_param(r), INT_MAX, 0);
  92     loco_update_rice_param(r, (v + 1) >> 1);
  93     if (!v) {
  94         if (r->save >= 0) {
  95             r->run = get_ur_golomb_jpegls(&r->gb, 2, INT_MAX, 0);
  96             if (r->run > 1)
  97                 r->save += r->run + 1;
  98             else
  99                 r->save -= 3;
 100         } else
 101             r->run2++;
 102     } else {
 103         v = ((v >> 1) + r->lossy) ^ -(v & 1);
 104         if (r->run2 > 0) {
 105             if (r->run2 > 2)
 106                 r->save += r->run2;
 107             else
 108                 r->save -= 3;
 109             r->run2 = 0;
 110         }
 111     }
 112
 113     return v;
 114 }
 115
 116 /* LOCO main predictor - LOCO-I/JPEG-LS predictor */
 117 static inline int loco_predict(uint8_t* data, int stride, int step)
 118 {
 119     int a, b, c;
 120
 121     a = data[-stride];
 122     b = data[-step];
 123     c = data[-stride - step];
 124
 125     return mid_pred(a, a + b - c, b);
 126 }
 127
 128 static int loco_decode_plane(LOCOContext *l, uint8_t *data, int width, int height,
 129                              int stride, const uint8_t *buf, int buf_size, int step)
 130 {
 131     RICEContext rc;
 132     int val;
 133     int i, j;
 134
 135     init_get_bits(&rc.gb, buf, buf_size*8);
 136     rc.save  = 0;
 137     rc.run   = 0;
 138     rc.run2  = 0;
 139     rc.lossy = l->lossy;
 140
 141     rc.sum   = 8;
 142     rc.count = 1;
 143
 144     /* restore top left pixel */
 145     val     = loco_get_rice(&rc);
 146     data[0] = 128 + val;
 147     /* restore top line */
 148     for (i = 1; i < width; i++) {
 149         val = loco_get_rice(&rc);
 150         data[i * step] = data[i * step - step] + val;
 151     }
 152     data += stride;
 153     for (j = 1; j < height; j++) {
 154         /* restore left column */
 155         val = loco_get_rice(&rc);
 156         data[0] = data[-stride] + val;
 157         /* restore all other pixels */
 158         for (i = 1; i < width; i++) {
 159             val = loco_get_rice(&rc);
 160             data[i * step] = loco_predict(&data[i * step], stride, step) + val;
 161         }
 162         data += stride;
 163     }
 164
 165     return (get_bits_count(&rc.gb) + 7) >> 3;
 166 }
 167
 168 static int decode_frame(AVCodecContext *avctx,
 169                         void *data, int *got_frame,
 170                         AVPacket *avpkt)
 171 {
 172     LOCOContext * const l = avctx->priv_data;
 173     const uint8_t *buf    = avpkt->data;
 174     int buf_size          = avpkt->size;
 175     AVFrame * const p     = data;
 176     int decoded, ret;
 177
 178     if ((ret = ff_get_buffer(avctx, p, 0)) < 0) {
 179         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 180         return ret;
 181     }
 182     p->key_frame = 1;
 183
 184     switch(l->mode) {
 185     case LOCO_CYUY2: case LOCO_YUY2: case LOCO_UYVY:
 186         decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
 187                                     p->linesize[0], buf, buf_size, 1);
 188         if (decoded >= buf_size)
 189             goto buf_too_small;
 190         buf += decoded; buf_size -= decoded;
 191
 192         decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height,
 193                                     p->linesize[1], buf, buf_size, 1);
 194         if (decoded >= buf_size)
 195             goto buf_too_small;
 196         buf += decoded; buf_size -= decoded;
 197
 198         decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height,
 199                                     p->linesize[2], buf, buf_size, 1);
 200         break;
 201     case LOCO_CYV12: case LOCO_YV12:
 202         decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
 203                                     p->linesize[0], buf, buf_size, 1);
 204         if (decoded >= buf_size)
 205             goto buf_too_small;
 206         buf += decoded; buf_size -= decoded;
 207
 208         decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height / 2,
 209                                     p->linesize[2], buf, buf_size, 1);
 210         if (decoded >= buf_size)
 211             goto buf_too_small;
 212         buf += decoded; buf_size -= decoded;
 213
 214         decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height / 2,
 215                                     p->linesize[1], buf, buf_size, 1);
 216         break;
 217     case LOCO_CRGB: case LOCO_RGB:
 218         decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
 219                                     -p->linesize[0], buf, buf_size, 3);
 220         if (decoded >= buf_size)
 221             goto buf_too_small;
 222         buf += decoded; buf_size -= decoded;
 223
 224         decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 1, avctx->width, avctx->height,
 225                                     -p->linesize[0], buf, buf_size, 3);
 226         if (decoded >= buf_size)
 227             goto buf_too_small;
 228         buf += decoded; buf_size -= decoded;
 229
 230         decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 2, avctx->width, avctx->height,
 231                                     -p->linesize[0], buf, buf_size, 3);
 232         break;
 233     case LOCO_RGBA:
 234         decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
 235                                     p->linesize[0], buf, buf_size, 4);
 236         if (decoded >= buf_size)
 237             goto buf_too_small;
 238         buf += decoded; buf_size -= decoded;
 239
 240         decoded = loco_decode_plane(l, p->data[0] + 1, avctx->width, avctx->height,
 241                                     p->linesize[0], buf, buf_size, 4);
 242         if (decoded >= buf_size)
 243             goto buf_too_small;
 244         buf += decoded; buf_size -= decoded;
 245
 246         decoded = loco_decode_plane(l, p->data[0] + 2, avctx->width, avctx->height,
 247                                     p->linesize[0], buf, buf_size, 4);
 248         if (decoded >= buf_size)
 249             goto buf_too_small;
 250         buf += decoded; buf_size -= decoded;
 251
 252         decoded = loco_decode_plane(l, p->data[0] + 3, avctx->width, avctx->height,
 253                                     p->linesize[0], buf, buf_size, 4);
 254         break;
 255     }
 256
 257     *got_frame      = 1;
 258
 259     return buf_size;
 260 buf_too_small:
 261     av_log(avctx, AV_LOG_ERROR, "Input data too small.\n");
 262     return AVERROR(EINVAL);
 263 }
 264
 265 static av_cold int decode_init(AVCodecContext *avctx)
 266 {
 267     LOCOContext * const l = avctx->priv_data;
 268     int version;
 269
 270     l->avctx = avctx;
 271     if (avctx->extradata_size < 12) {
 272         av_log(avctx, AV_LOG_ERROR, "Extradata size must be >= 12 instead of %i\n",
 273                avctx->extradata_size);
 274         return AVERROR_INVALIDDATA;
 275     }
 276     version = AV_RL32(avctx->extradata);
 277     switch (version) {
 278     case 1:
 279         l->lossy = 0;
 280         break;
 281     case 2:
 282         l->lossy = AV_RL32(avctx->extradata + 8);
 283         break;
 284     default:
 285         l->lossy = AV_RL32(avctx->extradata + 8);
 286         av_log_ask_for_sample(avctx, "This is LOCO codec version %i.\n", version);
 287     }
 288
 289     l->mode = AV_RL32(avctx->extradata + 4);
 290     switch (l->mode) {
 291     case LOCO_CYUY2:
 292     case LOCO_YUY2:
 293     case LOCO_UYVY:
 294         avctx->pix_fmt = AV_PIX_FMT_YUV422P;
 295         break;
 296     case LOCO_CRGB:
 297     case LOCO_RGB:
 298         avctx->pix_fmt = AV_PIX_FMT_BGR24;
 299         break;
 300     case LOCO_CYV12:
 301     case LOCO_YV12:
 302         avctx->pix_fmt = AV_PIX_FMT_YUV420P;
 303         break;
 304     case LOCO_CRGBA:
 305     case LOCO_RGBA:
 306         avctx->pix_fmt = AV_PIX_FMT_RGB32;
 307         break;
 308     default:
 309         av_log(avctx, AV_LOG_INFO, "Unknown colorspace, index = %i\n", l->mode);
 310         return AVERROR_INVALIDDATA;
 311     }
 312     if (avctx->debug & FF_DEBUG_PICT_INFO)
 313         av_log(avctx, AV_LOG_INFO, "lossy:%i, version:%i, mode: %i\n", l->lossy, version, l->mode);
 314
 315     return 0;
 316 }
 317
 318 AVCodec ff_loco_decoder = {
 319     .name           = "loco",
 320     .type           = AVMEDIA_TYPE_VIDEO,
 321     .id             = AV_CODEC_ID_LOCO,
 322     .priv_data_size = sizeof(LOCOContext),
 323     .init           = decode_init,
 324     .decode         = decode_frame,
 325     .capabilities   = CODEC_CAP_DR1,
 326     .long_name      = NULL_IF_CONFIG_SMALL("LOCO"),
 327 };