libdiracdec.c
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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 Libav.
7  *
8  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
31 #include "libavutil/imgutils.h"
32 #include "libdirac.h"
33 
34 #undef NDEBUG
35 #include <assert.h>
36 
37 #include <libdirac_decoder/dirac_parser.h>
38 
40 typedef struct DiracDecoderParams {
42  dirac_decoder_t* p_decoder;
43 
45  unsigned char* p_out_frame_buf;
47 
48 
52 static enum PixelFormat get_chroma_format(dirac_chroma_t dirac_pix_fmt)
53 {
54  int num_formats = sizeof(dirac_pixel_format_map) /
55  sizeof(dirac_pixel_format_map[0]);
56  int idx;
57 
58  for (idx = 0; idx < num_formats; ++idx)
59  if (dirac_pixel_format_map[idx].dirac_pix_fmt == dirac_pix_fmt)
60  return dirac_pixel_format_map[idx].ff_pix_fmt;
61  return PIX_FMT_NONE;
62 }
63 
65 {
66 
67  DiracDecoderParams *p_dirac_params = avccontext->priv_data;
68  p_dirac_params->p_decoder = dirac_decoder_init(avccontext->debug);
69 
70  if (!p_dirac_params->p_decoder)
71  return -1;
72 
73  return 0;
74 }
75 
76 static int libdirac_decode_frame(AVCodecContext *avccontext,
77  void *data, int *data_size,
78  AVPacket *avpkt)
79 {
80  const uint8_t *buf = avpkt->data;
81  int buf_size = avpkt->size;
82 
83  DiracDecoderParams *p_dirac_params = avccontext->priv_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  case STATE_BUFFER:
102  return buf_size;
103 
104  case STATE_SEQUENCE:
105  {
106  /* tell Libav about sequence details */
107  dirac_sourceparams_t *src_params = &p_dirac_params->p_decoder->src_params;
108 
109  if (av_image_check_size(src_params->width, src_params->height,
110  0, avccontext) < 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 = get_chroma_format(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)
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 
176 {
177  DiracDecoderParams *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 
198  .name = "libdirac",
199  .type = AVMEDIA_TYPE_VIDEO,
200  .id = CODEC_ID_DIRAC,
201  .priv_data_size = sizeof(DiracDecoderParams),
205  .capabilities = CODEC_CAP_DELAY,
207  .long_name = NULL_IF_CONFIG_SMALL("libdirac Dirac 2.2"),
208 };