FFmpeg
yop.c
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1 /*
2  * Psygnosis YOP demuxer
3  *
4  * Copyright (C) 2010 Mohamed Naufal Basheer <naufal11@gmail.com>
5  * derived from the code by
6  * Copyright (C) 2009 Thomas P. Higdon <thomas.p.higdon@gmail.com>
7  *
8  * This file is part of FFmpeg.
9  *
10  * FFmpeg is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU Lesser General Public
12  * License as published by the Free Software Foundation; either
13  * version 2.1 of the License, or (at your option) any later version.
14  *
15  * FFmpeg is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18  * Lesser General Public License for more details.
19  *
20  * You should have received a copy of the GNU Lesser General Public
21  * License along with FFmpeg; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23  */
24 
26 #include "libavutil/intreadwrite.h"
27 #include "avformat.h"
28 #include "internal.h"
29 
30 typedef struct yop_dec_context {
32 
33  int odd_frame;
38 
39 static int yop_probe(const AVProbeData *probe_packet)
40 {
41  if (AV_RB16(probe_packet->buf) == AV_RB16("YO") &&
42  probe_packet->buf[2]<10 &&
43  probe_packet->buf[3]<10 &&
44  probe_packet->buf[6] &&
45  probe_packet->buf[7] &&
46  !(probe_packet->buf[8] & 1) &&
47  !(probe_packet->buf[10] & 1) &&
48  AV_RL16(probe_packet->buf + 12 + 6) >= 920 &&
49  AV_RL16(probe_packet->buf + 12 + 6) < probe_packet->buf[12] * 3 + 4 + probe_packet->buf[7] * 2048
50  )
51  return AVPROBE_SCORE_MAX * 3 / 4;
52 
53  return 0;
54 }
55 
57 {
58  YopDecContext *yop = s->priv_data;
59  AVIOContext *pb = s->pb;
60 
61  AVCodecParameters *audio_par, *video_par;
63 
64  int frame_rate, ret;
65 
66  audio_stream = avformat_new_stream(s, NULL);
67  video_stream = avformat_new_stream(s, NULL);
68  if (!audio_stream || !video_stream)
69  return AVERROR(ENOMEM);
70 
71  // Audio
72  audio_par = audio_stream->codecpar;
73  audio_par->codec_type = AVMEDIA_TYPE_AUDIO;
75  audio_par->channels = 1;
76  audio_par->channel_layout = AV_CH_LAYOUT_MONO;
77  audio_par->sample_rate = 22050;
78 
79  // Video
80  video_par = video_stream->codecpar;
81  video_par->codec_type = AVMEDIA_TYPE_VIDEO;
82  video_par->codec_id = AV_CODEC_ID_YOP;
83 
84  avio_skip(pb, 6);
85 
86  frame_rate = avio_r8(pb);
87  yop->frame_size = avio_r8(pb) * 2048;
88  video_par->width = avio_rl16(pb);
89  video_par->height = avio_rl16(pb);
90 
91  video_stream->sample_aspect_ratio = (AVRational){1, 2};
92 
93  ret = ff_get_extradata(s, video_par, pb, 8);
94  if (ret < 0)
95  return ret;
96 
97  yop->palette_size = video_par->extradata[0] * 3 + 4;
98  yop->audio_block_length = AV_RL16(video_par->extradata + 6);
99 
100  video_par->bit_rate = 8 * (yop->frame_size - yop->audio_block_length) * frame_rate;
101 
102  // 1840 samples per frame, 1 nibble per sample; hence 1840/2 = 920
103  if (yop->audio_block_length < 920 ||
104  yop->audio_block_length + yop->palette_size >= yop->frame_size) {
105  av_log(s, AV_LOG_ERROR, "YOP has invalid header\n");
106  return AVERROR_INVALIDDATA;
107  }
108 
109  avio_seek(pb, 2048, SEEK_SET);
110 
111  avpriv_set_pts_info(video_stream, 32, 1, frame_rate);
112 
113  return 0;
114 }
115 
117 {
118  YopDecContext *yop = s->priv_data;
119  AVIOContext *pb = s->pb;
120 
121  int ret;
122  int actual_video_data_size = yop->frame_size -
123  yop->audio_block_length - yop->palette_size;
124 
125  yop->video_packet.stream_index = 1;
126 
127  if (yop->video_packet.data) {
128  av_packet_move_ref(pkt, &yop->video_packet);
129  pkt->data[0] = yop->odd_frame;
130  pkt->flags |= AV_PKT_FLAG_KEY;
131  yop->odd_frame ^= 1;
132  return 0;
133  }
134  ret = av_new_packet(&yop->video_packet,
135  yop->frame_size - yop->audio_block_length);
136  if (ret < 0)
137  return ret;
138 
139  yop->video_packet.pos = avio_tell(pb);
140 
141  ret = avio_read(pb, yop->video_packet.data, yop->palette_size);
142  if (ret < 0) {
143  goto err_out;
144  }else if (ret < yop->palette_size) {
145  ret = AVERROR_EOF;
146  goto err_out;
147  }
148 
149  ret = av_get_packet(pb, pkt, 920);
150  if (ret < 0)
151  goto err_out;
152 
153  // Set position to the start of the frame
154  pkt->pos = yop->video_packet.pos;
155 
156  avio_skip(pb, yop->audio_block_length - ret);
157 
158  ret = avio_read(pb, yop->video_packet.data + yop->palette_size,
159  actual_video_data_size);
160  if (ret < 0)
161  goto err_out;
162  else if (ret < actual_video_data_size)
163  av_shrink_packet(&yop->video_packet, yop->palette_size + ret);
164 
165  // Arbitrarily return the audio data first
166  return 0;
167 
168 err_out:
170  return ret;
171 }
172 
174 {
175  YopDecContext *yop = s->priv_data;
177  return 0;
178 }
179 
180 static int yop_read_seek(AVFormatContext *s, int stream_index,
181  int64_t timestamp, int flags)
182 {
183  YopDecContext *yop = s->priv_data;
184  int64_t frame_pos, pos_min, pos_max;
185  int frame_count;
186 
187  if (!stream_index)
188  return -1;
189 
190  pos_min = s->internal->data_offset;
191  pos_max = avio_size(s->pb) - yop->frame_size;
192  frame_count = (pos_max - pos_min) / yop->frame_size;
193 
194  timestamp = FFMAX(0, FFMIN(frame_count, timestamp));
195 
196  frame_pos = timestamp * yop->frame_size + pos_min;
197 
198  if (avio_seek(s->pb, frame_pos, SEEK_SET) < 0)
199  return -1;
200 
202  yop->odd_frame = timestamp & 1;
203 
204  return 0;
205 }
206 
208  .name = "yop",
209  .long_name = NULL_IF_CONFIG_SMALL("Psygnosis YOP"),
210  .priv_data_size = sizeof(YopDecContext),
216  .extensions = "yop",
218 };
#define NULL
Definition: coverity.c:32
Bytestream IO Context.
Definition: avio.h:161
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:346
static int yop_read_header(AVFormatContext *s)
Definition: yop.c:56
static int yop_read_close(AVFormatContext *s)
Definition: yop.c:173
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:383
void av_shrink_packet(AVPacket *pkt, int size)
Reduce packet size, correctly zeroing padding.
Definition: avpacket.c:103
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4869
int64_t data_offset
offset of the first packet
Definition: internal.h:80
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:153
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition: avformat.h:938
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:253
AVFormatInternal * internal
An opaque field for libavformat internal usage.
Definition: avformat.h:1804
static AVStream * video_stream
AVPacket video_packet
Definition: yop.c:31
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:341
static AVPacket pkt
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
Definition: bytestream.h:87
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:87
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
Format I/O context.
Definition: avformat.h:1351
int width
Video only.
Definition: codec_par.h:126
int palette_size
Definition: yop.c:36
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4450
uint8_t * data
Definition: packet.h:363
void av_packet_move_ref(AVPacket *dst, AVPacket *src)
Move every field in src to dst and reset src.
Definition: avpacket.c:664
#define AVERROR_EOF
End of file.
Definition: error.h:55
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:305
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
uint64_t channel_layout
Audio only.
Definition: codec_par.h:162
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:637
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:89
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:401
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:88
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
static AVStream * audio_stream
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:153
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
#define FFMAX(a, b)
Definition: common.h:94
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:369
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:628
static int yop_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: yop.c:116
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
static int yop_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: yop.c:180
int audio_block_length
Definition: yop.c:35
int frame_size
Definition: yop.c:34
audio channel layout utility functions
#define FFMIN(a, b)
Definition: common.h:96
AVInputFormat ff_yop_demuxer
Definition: yop.c:207
#define s(width, name)
Definition: cbs_vp9.c:257
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
Stream structure.
Definition: avformat.h:876
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVIOContext * pb
I/O context.
Definition: avformat.h:1393
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:606
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:463
Rational number (pair of numerator and denominator).
Definition: rational.h:58
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
#define flags(name, subs,...)
Definition: cbs_av1.c:560
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
int sample_rate
Audio only.
Definition: codec_par.h:170
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
static int yop_probe(const AVProbeData *probe_packet)
Definition: yop.c:39
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:743
Main libavformat public API header.
int ff_get_extradata(AVFormatContext *s, AVCodecParameters *par, AVIOContext *pb, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0 and f...
Definition: utils.c:3277
void * priv_data
Format private data.
Definition: avformat.h:1379
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
int channels
Audio only.
Definition: codec_par.h:166
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:650
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1023
int odd_frame
Definition: yop.c:33
int stream_index
Definition: packet.h:365
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
#define AV_CH_LAYOUT_MONO
This structure stores compressed data.
Definition: packet.h:340