FFmpeg  4.0
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_packet_unref(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)
186  return AVERROR(ENOMEM);
189  avs->st_video->codecpar->width = avs->width;
190  avs->st_video->codecpar->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)
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 };
#define NULL
Definition: coverity.c:32
int width
Definition: avs.c:30
const char * s
Definition: avisynth_c.h:768
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int ff_voc_get_packet(AVFormatContext *s, AVPacket *pkt, AVStream *st, int max_size)
Definition: voc_packet.c:27
int size
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3884
int index
stream index in AVFormatContext
Definition: avformat.h:874
int size
Definition: avcodec.h:1431
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:331
static AVPacket pkt
int ctx_flags
Flags signalling stream properties.
Definition: avformat.h:1391
Format I/O context.
Definition: avformat.h:1342
AVStream * st_video
Definition: avs.c:28
uint8_t
int remaining_audio_size
Definition: avs.c:36
int width
Video only.
Definition: avcodec.h:3950
#define AVFMTCTX_NOHEADER
signal that no header is present (streams are added dynamically)
Definition: avformat.h:1286
static int avs_read_close(AVFormatContext *s)
Definition: avs.c:221
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4441
uint8_t * data
Definition: avcodec.h:1430
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:648
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1462
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:86
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
Definition: avs.c:26
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:770
#define AVERROR(e)
Definition: error.h:43
VocDecContext voc
Definition: avs.c:27
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
Definition: avs.c:31
AVInputFormat ff_avs_demuxer
Definition: avs.c:226
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3880
int nb_frames
Definition: avs.c:34
int fps
Definition: avs.c:33
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:946
Definition: avs.c:40
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1436
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:639
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:450
int remaining_frame_size
Definition: avs.c:35
static int avs_read_video_packet(AVFormatContext *s, AVPacket *pkt, AvsBlockType type, int sub_type, int size, uint8_t *palette, int palette_size)
Definition: avs.c:86
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
static int avs_probe(AVProbeData *p)
Definition: avs.c:47
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
Stream structure.
Definition: avformat.h:873
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVStream * st_audio
Definition: avs.c:29
AVIOContext * pb
I/O context.
Definition: avformat.h:1384
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:592
static int avs_read_audio_packet(AVFormatContext *s, AVPacket *pkt)
Definition: avs.c:123
Rational number (pair of numerator and denominator).
Definition: rational.h:58
cl_device_type type
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:458
AvsBlockType
Definition: avs.c:30
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
static int avs_read_header(AVFormatContext *s)
Definition: avs.c:60
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:754
Main libavformat public API header.
Definition: avs.c:32
int bits_per_sample
Definition: avs.c:32
int height
Definition: avs.c:31
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:924
void * priv_data
Format private data.
Definition: avformat.h:1370
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: avcodec.h:3926
static int avs_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: avs.c:144
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:647
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1020
int stream_index
Definition: avcodec.h:1432
AVRational r_frame_rate
Real base framerate of the stream.
Definition: avformat.h:997
This structure stores compressed data.
Definition: avcodec.h:1407