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avs.c
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1 /*
2  * AVS demuxer.
3  * Copyright (c) 2006 Aurelien Jacobs <aurel@gnuage.org>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "avformat.h"
23 #include "voc.h"
24 
25 
26 typedef struct avs_format {
30  int width;
31  int height;
33  int fps;
34  int nb_frames;
37 } AvsFormat;
38 
39 typedef enum avs_block_type {
40  AVS_NONE = 0x00,
41  AVS_VIDEO = 0x01,
42  AVS_AUDIO = 0x02,
43  AVS_PALETTE = 0x03,
44  AVS_GAME_DATA = 0x04,
45 } AvsBlockType;
46 
47 static int avs_probe(AVProbeData * p)
48 {
49  const uint8_t *d;
50 
51  d = p->buf;
52  if (d[0] == 'w' && d[1] == 'W' && d[2] == 0x10 && d[3] == 0)
53  /* Ensure the buffer probe scores higher than the extension probe.
54  * This avoids problems with misdetection as AviSynth scripts. */
55  return AVPROBE_SCORE_EXTENSION + 5;
56 
57  return 0;
58 }
59 
61 {
62  AvsFormat *avs = s->priv_data;
63 
65 
66  avio_skip(s->pb, 4);
67  avs->width = avio_rl16(s->pb);
68  avs->height = avio_rl16(s->pb);
69  avs->bits_per_sample = avio_rl16(s->pb);
70  avs->fps = avio_rl16(s->pb);
71  avs->nb_frames = avio_rl32(s->pb);
72  avs->remaining_frame_size = 0;
73  avs->remaining_audio_size = 0;
74 
75  avs->st_video = avs->st_audio = NULL;
76 
77  if (avs->width != 318 || avs->height != 198)
78  av_log(s, AV_LOG_ERROR, "This avs pretend to be %dx%d "
79  "when the avs format is supposed to be 318x198 only.\n",
80  avs->width, avs->height);
81 
82  return 0;
83 }
84 
85 static int
87  AvsBlockType type, int sub_type, int size,
88  uint8_t * palette, int palette_size)
89 {
90  AvsFormat *avs = s->priv_data;
91  int ret;
92 
93  ret = av_new_packet(pkt, size + palette_size);
94  if (ret < 0)
95  return ret;
96 
97  if (palette_size) {
98  pkt->data[0] = 0x00;
99  pkt->data[1] = 0x03;
100  pkt->data[2] = palette_size & 0xFF;
101  pkt->data[3] = (palette_size >> 8) & 0xFF;
102  memcpy(pkt->data + 4, palette, palette_size - 4);
103  }
104 
105  pkt->data[palette_size + 0] = sub_type;
106  pkt->data[palette_size + 1] = type;
107  pkt->data[palette_size + 2] = size & 0xFF;
108  pkt->data[palette_size + 3] = (size >> 8) & 0xFF;
109  ret = avio_read(s->pb, pkt->data + palette_size + 4, size - 4) + 4;
110  if (ret < size) {
111  av_free_packet(pkt);
112  return AVERROR(EIO);
113  }
114 
115  pkt->size = ret + palette_size;
116  pkt->stream_index = avs->st_video->index;
117  if (sub_type == 0)
118  pkt->flags |= AV_PKT_FLAG_KEY;
119 
120  return 0;
121 }
122 
124 {
125  AvsFormat *avs = s->priv_data;
126  int ret, size;
127 
128  size = avio_tell(s->pb);
129  ret = ff_voc_get_packet(s, pkt, avs->st_audio, avs->remaining_audio_size);
130  size = avio_tell(s->pb) - size;
131  avs->remaining_audio_size -= size;
132 
133  if (ret == AVERROR(EIO))
134  return 0; /* this indicate EOS */
135  if (ret < 0)
136  return ret;
137 
138  pkt->stream_index = avs->st_audio->index;
139  pkt->flags |= AV_PKT_FLAG_KEY;
140 
141  return size;
142 }
143 
145 {
146  AvsFormat *avs = s->priv_data;
147  int sub_type = 0, size = 0;
149  int palette_size = 0;
150  uint8_t palette[4 + 3 * 256];
151  int ret;
152 
153  if (avs->remaining_audio_size > 0)
154  if (avs_read_audio_packet(s, pkt) > 0)
155  return 0;
156 
157  while (1) {
158  if (avs->remaining_frame_size <= 0) {
159  if (!avio_rl16(s->pb)) /* found EOF */
160  return AVERROR(EIO);
161  avs->remaining_frame_size = avio_rl16(s->pb) - 4;
162  }
163 
164  while (avs->remaining_frame_size > 0) {
165  sub_type = avio_r8(s->pb);
166  type = avio_r8(s->pb);
167  size = avio_rl16(s->pb);
168  if (size < 4)
169  return AVERROR_INVALIDDATA;
170  avs->remaining_frame_size -= size;
171 
172  switch (type) {
173  case AVS_PALETTE:
174  if (size - 4 > sizeof(palette))
175  return AVERROR_INVALIDDATA;
176  ret = avio_read(s->pb, palette, size - 4);
177  if (ret < size - 4)
178  return AVERROR(EIO);
179  palette_size = size;
180  break;
181 
182  case AVS_VIDEO:
183  if (!avs->st_video) {
184  avs->st_video = avformat_new_stream(s, NULL);
185  if (avs->st_video == NULL)
186  return AVERROR(ENOMEM);
189  avs->st_video->codec->width = avs->width;
190  avs->st_video->codec->height = avs->height;
192  avs->st_video->nb_frames = avs->nb_frames;
193 #if FF_API_R_FRAME_RATE
194  avs->st_video->r_frame_rate =
195 #endif
196  avs->st_video->avg_frame_rate = (AVRational){avs->fps, 1};
197  }
198  return avs_read_video_packet(s, pkt, type, sub_type, size,
199  palette, palette_size);
200 
201  case AVS_AUDIO:
202  if (!avs->st_audio) {
203  avs->st_audio = avformat_new_stream(s, NULL);
204  if (avs->st_audio == NULL)
205  return AVERROR(ENOMEM);
207  }
208  avs->remaining_audio_size = size - 4;
209  size = avs_read_audio_packet(s, pkt);
210  if (size != 0)
211  return size;
212  break;
213 
214  default:
215  avio_skip(s->pb, size - 4);
216  }
217  }
218  }
219 }
220 
222 {
223  return 0;
224 }
225 
227  .name = "avs",
228  .long_name = NULL_IF_CONFIG_SMALL("AVS"),
229  .priv_data_size = sizeof(AvsFormat),
234 };