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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  return 50;
54 
55  return 0;
56 }
57 
59 {
60  AvsFormat *avs = s->priv_data;
61 
63 
64  avio_skip(s->pb, 4);
65  avs->width = avio_rl16(s->pb);
66  avs->height = avio_rl16(s->pb);
67  avs->bits_per_sample = avio_rl16(s->pb);
68  avs->fps = avio_rl16(s->pb);
69  avs->nb_frames = avio_rl32(s->pb);
70  avs->remaining_frame_size = 0;
71  avs->remaining_audio_size = 0;
72 
73  avs->st_video = avs->st_audio = NULL;
74 
75  if (avs->width != 318 || avs->height != 198)
76  av_log(s, AV_LOG_ERROR, "This avs pretend to be %dx%d "
77  "when the avs format is supposed to be 318x198 only.\n",
78  avs->width, avs->height);
79 
80  return 0;
81 }
82 
83 static int
85  AvsBlockType type, int sub_type, int size,
86  uint8_t * palette, int palette_size)
87 {
88  AvsFormat *avs = s->priv_data;
89  int ret;
90 
91  ret = av_new_packet(pkt, size + palette_size);
92  if (ret < 0)
93  return ret;
94 
95  if (palette_size) {
96  pkt->data[0] = 0x00;
97  pkt->data[1] = 0x03;
98  pkt->data[2] = palette_size & 0xFF;
99  pkt->data[3] = (palette_size >> 8) & 0xFF;
100  memcpy(pkt->data + 4, palette, palette_size - 4);
101  }
102 
103  pkt->data[palette_size + 0] = sub_type;
104  pkt->data[palette_size + 1] = type;
105  pkt->data[palette_size + 2] = size & 0xFF;
106  pkt->data[palette_size + 3] = (size >> 8) & 0xFF;
107  ret = avio_read(s->pb, pkt->data + palette_size + 4, size - 4) + 4;
108  if (ret < size) {
109  av_free_packet(pkt);
110  return AVERROR(EIO);
111  }
112 
113  pkt->size = ret + palette_size;
114  pkt->stream_index = avs->st_video->index;
115  if (sub_type == 0)
116  pkt->flags |= AV_PKT_FLAG_KEY;
117 
118  return 0;
119 }
120 
122 {
123  AvsFormat *avs = s->priv_data;
124  int ret, size;
125 
126  size = avio_tell(s->pb);
127  ret = ff_voc_get_packet(s, pkt, avs->st_audio, avs->remaining_audio_size);
128  size = avio_tell(s->pb) - size;
129  avs->remaining_audio_size -= size;
130 
131  if (ret == AVERROR(EIO))
132  return 0; /* this indicate EOS */
133  if (ret < 0)
134  return ret;
135 
136  pkt->stream_index = avs->st_audio->index;
137  pkt->flags |= AV_PKT_FLAG_KEY;
138 
139  return size;
140 }
141 
143 {
144  AvsFormat *avs = s->priv_data;
145  int sub_type = 0, size = 0;
146  AvsBlockType type = AVS_NONE;
147  int palette_size = 0;
148  uint8_t palette[4 + 3 * 256];
149  int ret;
150 
151  if (avs->remaining_audio_size > 0)
152  if (avs_read_audio_packet(s, pkt) > 0)
153  return 0;
154 
155  while (1) {
156  if (avs->remaining_frame_size <= 0) {
157  if (!avio_rl16(s->pb)) /* found EOF */
158  return AVERROR(EIO);
159  avs->remaining_frame_size = avio_rl16(s->pb) - 4;
160  }
161 
162  while (avs->remaining_frame_size > 0) {
163  sub_type = avio_r8(s->pb);
164  type = avio_r8(s->pb);
165  size = avio_rl16(s->pb);
166  if (size < 4)
167  return AVERROR_INVALIDDATA;
168  avs->remaining_frame_size -= size;
169 
170  switch (type) {
171  case AVS_PALETTE:
172  if (size - 4 > sizeof(palette))
173  return AVERROR_INVALIDDATA;
174  ret = avio_read(s->pb, palette, size - 4);
175  if (ret < size - 4)
176  return AVERROR(EIO);
177  palette_size = size;
178  break;
179 
180  case AVS_VIDEO:
181  if (!avs->st_video) {
182  avs->st_video = avformat_new_stream(s, NULL);
183  if (avs->st_video == NULL)
184  return AVERROR(ENOMEM);
187  avs->st_video->codec->width = avs->width;
188  avs->st_video->codec->height = avs->height;
190  avs->st_video->nb_frames = avs->nb_frames;
191 #if FF_API_R_FRAME_RATE
192  avs->st_video->r_frame_rate =
193 #endif
194  avs->st_video->avg_frame_rate = (AVRational){avs->fps, 1};
195  }
196  return avs_read_video_packet(s, pkt, type, sub_type, size,
197  palette, palette_size);
198 
199  case AVS_AUDIO:
200  if (!avs->st_audio) {
201  avs->st_audio = avformat_new_stream(s, NULL);
202  if (avs->st_audio == NULL)
203  return AVERROR(ENOMEM);
205  }
206  avs->remaining_audio_size = size - 4;
207  size = avs_read_audio_packet(s, pkt);
208  if (size != 0)
209  return size;
210  break;
211 
212  default:
213  avio_skip(s->pb, size - 4);
214  }
215  }
216  }
217 }
218 
220 {
221  return 0;
222 }
223 
225  .name = "avs",
226  .long_name = NULL_IF_CONFIG_SMALL("AVS"),
227  .priv_data_size = sizeof(AvsFormat),
232 };