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 "demux.h"
29 #include "internal.h"
30 
31 typedef struct yop_dec_context {
33 
34  int odd_frame;
39 
40 static int yop_probe(const AVProbeData *probe_packet)
41 {
42  if (AV_RB16(probe_packet->buf) == AV_RB16("YO") &&
43  probe_packet->buf[2]<10 &&
44  probe_packet->buf[3]<10 &&
45  probe_packet->buf[6] &&
46  probe_packet->buf[7] &&
47  !(probe_packet->buf[8] & 1) &&
48  !(probe_packet->buf[10] & 1) &&
49  AV_RL16(probe_packet->buf + 12 + 6) >= 920 &&
50  AV_RL16(probe_packet->buf + 12 + 6) < probe_packet->buf[12] * 3 + 4 + probe_packet->buf[7] * 2048
51  )
52  return AVPROBE_SCORE_MAX * 3 / 4;
53 
54  return 0;
55 }
56 
58 {
59  YopDecContext *yop = s->priv_data;
60  AVIOContext *pb = s->pb;
61 
62  AVCodecParameters *audio_par, *video_par;
64 
65  int frame_rate, ret;
66 
69  if (!audio_stream || !video_stream)
70  return AVERROR(ENOMEM);
71 
72  // Audio
73  audio_par = audio_stream->codecpar;
74  audio_par->codec_type = AVMEDIA_TYPE_AUDIO;
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 
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;
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:
169  av_packet_unref(&yop->video_packet);
170  return ret;
171 }
172 
174 {
175  YopDecContext *yop = s->priv_data;
176  av_packet_unref(&yop->video_packet);
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 = ffformatcontext(s)->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 
201  av_packet_unref(&yop->video_packet);
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 };
yop_read_header
static int yop_read_header(AVFormatContext *s)
Definition: yop.c:57
av_packet_unref
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:422
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:76
AVERROR
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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: options.c:243
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:58
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:54
ffformatcontext
static av_always_inline FFFormatContext * ffformatcontext(AVFormatContext *s)
Definition: internal.h:191
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
yop_read_packet
static int yop_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: yop.c:116
AVPacket::data
uint8_t * data
Definition: packet.h:374
yop_dec_context::frame_size
int frame_size
Definition: yop.c:35
yop_dec_context::audio_block_length
int audio_block_length
Definition: yop.c:36
FFMAX
#define FFMAX(a, b)
Definition: macros.h:47
AV_CODEC_ID_YOP
@ AV_CODEC_ID_YOP
Definition: codec_id.h:191
avio_size
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:344
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:429
ff_get_extradata
int ff_get_extradata(void *logctx, 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: demux_utils.c:355
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:463
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: avformat.c:771
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:151
av_shrink_packet
void av_shrink_packet(AVPacket *pkt, int size)
Reduce packet size, correctly zeroing padding.
Definition: avpacket.c:112
ff_yop_demuxer
const AVInputFormat ff_yop_demuxer
Definition: yop.c:207
yop_dec_context::video_packet
AVPacket video_packet
Definition: yop.c:32
read_close
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:143
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:500
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:480
avio_rl16
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:735
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AVInputFormat
Definition: avformat.h:546
yop_dec_context::palette_size
int palette_size
Definition: yop.c:37
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:41
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:256
av_new_packet
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:97
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:551
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:453
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:128
video_stream
static AVStream * video_stream
Definition: demux_decode.c:42
AV_CODEC_ID_ADPCM_IMA_APC
@ AV_CODEC_ID_ADPCM_IMA_APC
Definition: codec_id.h:394
FFFormatContext::data_offset
int64_t data_offset
offset of the first packet
Definition: internal.h:108
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:94
AVFormatContext
Format I/O context.
Definition: avformat.h:1104
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:861
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:545
NULL
#define NULL
Definition: coverity.c:32
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:213
av_packet_move_ref
void av_packet_move_ref(AVPacket *dst, AVPacket *src)
Move every field in src to dst and reset src.
Definition: avpacket.c:479
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:178
AVIOContext
Bytestream IO Context.
Definition: avio.h:166
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:115
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:301
audio_stream
static AVStream * audio_stream
Definition: demux_decode.c:42
AVStream::sample_aspect_ratio
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition: avformat.h:916
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:624
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:380
yop_read_close
static int yop_read_close(AVFormatContext *s)
Definition: yop.c:173
AVCodecParameters::height
int height
Definition: codec_par.h:129
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
demux.h
YopDecContext
Definition: yop.c:34
av_get_packet
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:102
yop_probe
static int yop_probe(const AVProbeData *probe_packet)
Definition: yop.c:40
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:838
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:252
avformat.h
channel_layout.h
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:633
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:339
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:29
AV_CHANNEL_LAYOUT_MONO
#define AV_CHANNEL_LAYOUT_MONO
Definition: channel_layout.h:368
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:62
AVPacket
This structure stores compressed data.
Definition: packet.h:351
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:394
yop_dec_context::odd_frame
int odd_frame
Definition: yop.c:34
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:91
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
yop_read_seek
static int yop_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: yop.c:180
yop_dec_context
Definition: yop.c:31
AV_RB16
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:98