extern/ffmpeg/libavcodec/oggtheora.c

   1 /**
   2     Copyright (C) 2005  Måns Rullgård
   3
   4     Permission is hereby granted, free of charge, to any person
   5     obtaining a copy of this software and associated documentation
   6     files (the "Software"), to deal in the Software without
   7     restriction, including without limitation the rights to use, copy,
   8     modify, merge, publish, distribute, sublicense, and/or sell copies
   9     of the Software, and to permit persons to whom the Software is
  10     furnished to do so, subject to the following conditions:
  11
  12     The above copyright notice and this permission notice shall be
  13     included in all copies or substantial portions of the Software.
  14
  15     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  16     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  17     MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  18     NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  19     HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  20     WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21     OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  22     DEALINGS IN THE SOFTWARE.
  23 **/
  24
  25 #include <stdlib.h>
  26 #include <theora/theora.h>
  27 #include "avcodec.h"
  28
  29 typedef struct TheoraContext {
  30     theora_info info;
  31     theora_state state;
  32     theora_comment comment;
  33     ogg_packet op;
  34 } TheoraContext;
  35
  36 static int
  37 Theora_decode_frame(AVCodecContext *ctx, void *outdata, int *outdata_size,
  38                     uint8_t *buf, int buf_size)
  39 {
  40     TheoraContext *thc = ctx->priv_data;
  41     AVFrame *frame = outdata;
  42     yuv_buffer yuv;
  43
  44     thc->op.packet = buf;
  45     thc->op.bytes = buf_size;
  46
  47     if(theora_decode_packetin(&thc->state, &thc->op))
  48         return -1;
  49
  50     theora_decode_YUVout(&thc->state, &yuv);
  51
  52     frame->data[0] = yuv.y;
  53     frame->data[1] = yuv.u;
  54     frame->data[2] = yuv.v;
  55     frame->linesize[0] = yuv.y_stride;
  56     frame->linesize[1] = yuv.uv_stride;
  57     frame->linesize[2] = yuv.uv_stride;
  58
  59     *outdata_size = sizeof(*frame);
  60     return buf_size;
  61 }
  62
  63 static int
  64 Theora_decode_end(AVCodecContext *ctx)
  65 {
  66     TheoraContext *thc = ctx->priv_data;
  67     theora_info_clear(&thc->info);
  68     theora_comment_clear(&thc->comment);
  69     return 0;
  70 }
  71
  72 static int
  73 Theora_decode_init(AVCodecContext *ctx)
  74 {
  75     TheoraContext *thc = ctx->priv_data;
  76     int size, hs, i;
  77     ogg_packet op;
  78     uint8_t *cdp;
  79
  80     if(ctx->extradata_size < 6)
  81         return -1;
  82
  83     theora_info_init(&thc->info);
  84
  85     memset(&op, 0, sizeof(op));
  86     cdp = ctx->extradata;
  87     size = ctx->extradata_size;
  88
  89     for(i = 0; i < 3; i++){
  90         hs = *cdp++ << 8;
  91         hs += *cdp++;
  92         size -= 2;
  93
  94         if(hs > size){
  95             av_log(ctx, AV_LOG_ERROR, "extradata too small: %i > %i\n",
  96                    hs, size);
  97             return -1;
  98         }
  99
 100         op.packet = cdp;
 101         op.bytes = hs;
 102         op.b_o_s = !i;
 103         if(theora_decode_header(&thc->info, &thc->comment, &op))
 104             return -1;
 105         op.packetno++;
 106
 107         cdp += hs;
 108         size -= hs;
 109     }
 110
 111     theora_decode_init(&thc->state, &thc->info);
 112
 113     ctx->width = thc->info.width;
 114     ctx->height = thc->info.height;
 115     ctx->time_base.num = thc->info.fps_denominator;
 116     ctx->time_base.den = thc->info.fps_numerator;
 117     ctx->pix_fmt = PIX_FMT_YUV420P; /* FIXME: others are possible */
 118
 119     return 0;
 120 }
 121
 122 AVCodec oggtheora_decoder = {
 123     "theora",
 124     CODEC_TYPE_VIDEO,
 125     CODEC_ID_THEORA,
 126     sizeof(TheoraContext),
 127     Theora_decode_init,
 128     NULL,
 129     Theora_decode_end,
 130     Theora_decode_frame,
 131     0,
 132     NULL
 133 };