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 libavcodec/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 av_cold 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         if ((buf[4] &0x08) == 0x08 && (buf[4] & 0x03))
  95             avccontext->has_b_frames = 1;
  96     }
  97     while (1) {
  98          /* parse data and process result */
  99         DecoderState state = dirac_parse (p_dirac_params->p_decoder);
 100         switch (state)
 101         {
 102         case STATE_BUFFER:
 103             return buf_size;
 104
 105         case STATE_SEQUENCE:
 106         {
 107             /* tell FFmpeg about sequence details */
 108             dirac_sourceparams_t *src_params =
 109                                   &p_dirac_params->p_decoder->src_params;
 110
 111             if (avcodec_check_dimensions(avccontext, src_params->width,
 112                                          src_params->height) < 0) {
 113                 av_log(avccontext, AV_LOG_ERROR, "Invalid dimensions (%dx%d)\n",
 114                        src_params->width, src_params->height);
 115                 avccontext->height = avccontext->width = 0;
 116                 return -1;
 117             }
 118
 119             avccontext->height = src_params->height;
 120             avccontext->width  = src_params->width;
 121
 122             avccontext->pix_fmt = GetFfmpegChromaFormat(src_params->chroma);
 123             if (avccontext->pix_fmt == PIX_FMT_NONE) {
 124                 av_log (avccontext, AV_LOG_ERROR,
 125                         "Dirac chroma format %d not supported currently\n",
 126                         src_params->chroma);
 127                 return -1;
 128             }
 129
 130             avccontext->time_base.den = src_params->frame_rate.numerator;
 131             avccontext->time_base.num = src_params->frame_rate.denominator;
 132
 133             /* calculate output dimensions */
 134             avpicture_fill(&pic, NULL, avccontext->pix_fmt,
 135                            avccontext->width, avccontext->height);
 136
 137             pict_size = avpicture_get_size(avccontext->pix_fmt,
 138                                            avccontext->width,
 139                                            avccontext->height);
 140
 141             /* allocate output buffer */
 142             if (p_dirac_params->p_out_frame_buf == NULL)
 143                 p_dirac_params->p_out_frame_buf = av_malloc (pict_size);
 144             buffer[0] = p_dirac_params->p_out_frame_buf;
 145             buffer[1] = p_dirac_params->p_out_frame_buf +
 146                         pic.linesize[0] * avccontext->height;
 147             buffer[2] = buffer[1] +
 148                         pic.linesize[1] * src_params->chroma_height;
 149
 150             /* tell Dirac about output destination */
 151             dirac_set_buf(p_dirac_params->p_decoder, buffer, NULL);
 152             break;
 153         }
 154         case STATE_SEQUENCE_END:
 155             break;
 156
 157         case STATE_PICTURE_AVAIL:
 158             /* fill picture with current buffer data from Dirac */
 159             avpicture_fill(picture, p_dirac_params->p_out_frame_buf,
 160                            avccontext->pix_fmt,
 161                            avccontext->width, avccontext->height);
 162             *data_size = sizeof(AVPicture);
 163             return buf_size;
 164
 165         case STATE_INVALID:
 166             return -1;
 167
 168         default:
 169             break;
 170         }
 171     }
 172
 173     return buf_size;
 174 }
 175
 176
 177 static av_cold int libdirac_decode_close(AVCodecContext *avccontext)
 178 {
 179     FfmpegDiracDecoderParams *p_dirac_params = avccontext->priv_data;
 180     dirac_decoder_close (p_dirac_params->p_decoder);
 181
 182     av_freep(&p_dirac_params->p_out_frame_buf);
 183
 184     return 0 ;
 185 }
 186
 187 static void libdirac_flush (AVCodecContext *avccontext)
 188 {
 189     /* Got a seek request. We will need free memory held in the private
 190      * context and free the current Dirac decoder handle and then open
 191      * a new decoder handle. */
 192     libdirac_decode_close (avccontext);
 193     libdirac_decode_init (avccontext);
 194     return;
 195 }
 196
 197
 198
 199 AVCodec libdirac_decoder = {
 200     "libdirac",
 201     CODEC_TYPE_VIDEO,
 202     CODEC_ID_DIRAC,
 203     sizeof(FfmpegDiracDecoderParams),
 204     libdirac_decode_init,
 205     NULL,
 206     libdirac_decode_close,
 207     libdirac_decode_frame,
 208     CODEC_CAP_DELAY,
 209     .flush = libdirac_flush,
 210     .long_name = NULL_IF_CONFIG_SMALL("libdirac Dirac 2.2"),
 211 } ;