libavcodec/libdiracdec.c

   1 /*
   2  * Dirac decoder support via libdirac library
   3  * Copyright (c) 2005 BBC, Andrew Kennedy <dirac at rd dot bbc dot co dot uk>
   4  * Copyright (c) 2006-2008 BBC, Anuradha Suraparaju <asuraparaju at gmail dot com >
   5  *
   6  * This file is part of FFmpeg.
   7  *
   8  * FFmpeg is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * FFmpeg is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with FFmpeg; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 /**
  24 * @file libdiracdec.c
  25 * Dirac decoder support via libdirac library; more details about the Dirac
  26 * project can be found at http://dirac.sourceforge.net/.
  27 * The libdirac_decoder library implements Dirac specification version 2.2
  28 * (http://dirac.sourceforge.net/specification.html).
  29 */
  30
  31 #include "libdirac.h"
  32
  33 #undef NDEBUG
  34 #include <assert.h>
  35
  36 #include <libdirac_decoder/dirac_parser.h>
  37
  38 /** contains a single frame returned from Dirac */
  39 typedef struct FfmpegDiracDecoderParams
  40 {
  41     /** decoder handle */
  42     dirac_decoder_t* p_decoder;
  43
  44     /** buffer to hold decoded frame */
  45     unsigned char* p_out_frame_buf;
  46 } FfmpegDiracDecoderParams;
  47
  48
  49 /**
  50 * returns FFmpeg chroma format
  51 */
  52 static enum PixelFormat GetFfmpegChromaFormat(dirac_chroma_t dirac_pix_fmt)
  53 {
  54     int num_formats = sizeof(ffmpeg_dirac_pixel_format_map) /
  55                       sizeof(ffmpeg_dirac_pixel_format_map[0]);
  56     int idx;
  57
  58     for (idx = 0; idx < num_formats; ++idx) {
  59         if (ffmpeg_dirac_pixel_format_map[idx].dirac_pix_fmt == dirac_pix_fmt) {
  60             return ffmpeg_dirac_pixel_format_map[idx].ff_pix_fmt;
  61         }
  62     }
  63     return PIX_FMT_NONE;
  64 }
  65
  66 static int libdirac_decode_init(AVCodecContext *avccontext)
  67 {
  68
  69     FfmpegDiracDecoderParams *p_dirac_params = avccontext->priv_data ;
  70     p_dirac_params->p_decoder =  dirac_decoder_init(avccontext->debug);
  71
  72     if (!p_dirac_params->p_decoder)
  73         return -1;
  74
  75     return 0 ;
  76 }
  77
  78 static int libdirac_decode_frame(AVCodecContext *avccontext,
  79                                  void *data, int *data_size,
  80                                  const uint8_t *buf, int buf_size)
  81 {
  82
  83     FfmpegDiracDecoderParams *p_dirac_params = avccontext->priv_data;
  84     AVPicture *picture = data;
  85     AVPicture pic;
  86     int pict_size;
  87     unsigned char *buffer[3];
  88
  89     *data_size = 0;
  90
  91     if (buf_size>0)
  92         /* set data to decode into buffer */
  93         dirac_buffer (p_dirac_params->p_decoder, buf, buf+buf_size);
  94
  95     while (1) {
  96          /* parse data and process result */
  97         DecoderState state = dirac_parse (p_dirac_params->p_decoder);
  98         switch (state)
  99         {
 100         case STATE_BUFFER:
 101             return buf_size;
 102
 103         case STATE_SEQUENCE:
 104         {
 105             /* tell FFmpeg about sequence details */
 106             dirac_sourceparams_t *src_params =
 107                                   &p_dirac_params->p_decoder->src_params;
 108
 109             if (avcodec_check_dimensions(avccontext, src_params->width,
 110                                          src_params->height) < 0) {
 111                 av_log(avccontext, AV_LOG_ERROR, "Invalid dimensions (%dx%d)\n",
 112                        src_params->width, src_params->height);
 113                 avccontext->height = avccontext->width = 0;
 114                 return -1;
 115             }
 116
 117             avccontext->height = src_params->height;
 118             avccontext->width  = src_params->width;
 119
 120             avccontext->pix_fmt = GetFfmpegChromaFormat(src_params->chroma);
 121             if (avccontext->pix_fmt == PIX_FMT_NONE) {
 122                 av_log (avccontext, AV_LOG_ERROR,
 123                         "Dirac chroma format %d not supported currently\n",
 124                         src_params->chroma);
 125                 return -1;
 126             }
 127
 128             avccontext->time_base.den = src_params->frame_rate.numerator;
 129             avccontext->time_base.num = src_params->frame_rate.denominator;
 130
 131             /* calculate output dimensions */
 132             avpicture_fill(&pic, NULL, avccontext->pix_fmt,
 133                            avccontext->width, avccontext->height);
 134
 135             pict_size = avpicture_get_size(avccontext->pix_fmt,
 136                                            avccontext->width,
 137                                            avccontext->height);
 138
 139             /* allocate output buffer */
 140             if (p_dirac_params->p_out_frame_buf == NULL)
 141                 p_dirac_params->p_out_frame_buf = av_malloc (pict_size);
 142             buffer[0] = p_dirac_params->p_out_frame_buf;
 143             buffer[1] = p_dirac_params->p_out_frame_buf +
 144                         pic.linesize[0] * avccontext->height;
 145             buffer[2] = buffer[1] +
 146                         pic.linesize[1] * src_params->chroma_height;
 147
 148             /* tell Dirac about output destination */
 149             dirac_set_buf(p_dirac_params->p_decoder, buffer, NULL);
 150             break;
 151         }
 152         case STATE_SEQUENCE_END:
 153             break;
 154
 155         case STATE_PICTURE_AVAIL:
 156             /* fill picture with current buffer data from Dirac */
 157             avpicture_fill(picture, p_dirac_params->p_out_frame_buf,
 158                            avccontext->pix_fmt,
 159                            avccontext->width, avccontext->height);
 160             *data_size = sizeof(AVPicture);
 161             return buf_size;
 162
 163         case STATE_INVALID:
 164             return -1;
 165
 166         default:
 167             break;
 168         }
 169     }
 170
 171     return buf_size;
 172 }
 173
 174
 175 static int libdirac_decode_close(AVCodecContext *avccontext)
 176 {
 177     FfmpegDiracDecoderParams *p_dirac_params = avccontext->priv_data;
 178     dirac_decoder_close (p_dirac_params->p_decoder);
 179
 180     av_freep(&p_dirac_params->p_out_frame_buf);
 181
 182     return 0 ;
 183 }
 184
 185 static void libdirac_flush (AVCodecContext *avccontext)
 186 {
 187     /* Got a seek request. We will need free memory held in the private
 188      * context and free the current Dirac decoder handle and then open
 189      * a new decoder handle. */
 190     libdirac_decode_close (avccontext);
 191     libdirac_decode_init (avccontext);
 192     return;
 193 }
 194
 195
 196
 197 AVCodec libdirac_decoder = {
 198     "libdirac",
 199     CODEC_TYPE_VIDEO,
 200     CODEC_ID_DIRAC,
 201     sizeof(FfmpegDiracDecoderParams),
 202     libdirac_decode_init,
 203     NULL,
 204     libdirac_decode_close,
 205     libdirac_decode_frame,
 206     CODEC_CAP_DELAY,
 207     .flush = libdirac_flush,
 208     .long_name = "libdirac Dirac 2.2",
 209 } ;