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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(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  // Extra data that will be passed to the decoder
72  if (ff_alloc_extradata(video_stream->codecpar, 8))
73  return AVERROR(ENOMEM);
74 
75  // Audio
76  audio_par = audio_stream->codecpar;
77  audio_par->codec_type = AVMEDIA_TYPE_AUDIO;
79  audio_par->channels = 1;
80  audio_par->channel_layout = AV_CH_LAYOUT_MONO;
81  audio_par->sample_rate = 22050;
82 
83  // Video
84  video_par = video_stream->codecpar;
85  video_par->codec_type = AVMEDIA_TYPE_VIDEO;
86  video_par->codec_id = AV_CODEC_ID_YOP;
87 
88  avio_skip(pb, 6);
89 
90  frame_rate = avio_r8(pb);
91  yop->frame_size = avio_r8(pb) * 2048;
92  video_par->width = avio_rl16(pb);
93  video_par->height = avio_rl16(pb);
94 
95  video_stream->sample_aspect_ratio = (AVRational){1, 2};
96 
97  ret = avio_read(pb, video_par->extradata, 8);
98  if (ret < 8)
99  return ret < 0 ? ret : AVERROR_EOF;
100 
101  yop->palette_size = video_par->extradata[0] * 3 + 4;
102  yop->audio_block_length = AV_RL16(video_par->extradata + 6);
103 
104  video_par->bit_rate = 8 * (yop->frame_size - yop->audio_block_length) * frame_rate;
105 
106  // 1840 samples per frame, 1 nibble per sample; hence 1840/2 = 920
107  if (yop->audio_block_length < 920 ||
108  yop->audio_block_length + yop->palette_size >= yop->frame_size) {
109  av_log(s, AV_LOG_ERROR, "YOP has invalid header\n");
110  return AVERROR_INVALIDDATA;
111  }
112 
113  avio_seek(pb, 2048, SEEK_SET);
114 
115  avpriv_set_pts_info(video_stream, 32, 1, frame_rate);
116 
117  return 0;
118 }
119 
121 {
122  YopDecContext *yop = s->priv_data;
123  AVIOContext *pb = s->pb;
124 
125  int ret;
126  int actual_video_data_size = yop->frame_size -
127  yop->audio_block_length - yop->palette_size;
128 
129  yop->video_packet.stream_index = 1;
130 
131  if (yop->video_packet.data) {
132  *pkt = yop->video_packet;
133  yop->video_packet.data = NULL;
134  yop->video_packet.buf = NULL;
135  yop->video_packet.size = 0;
136  pkt->data[0] = yop->odd_frame;
137  pkt->flags |= AV_PKT_FLAG_KEY;
138  yop->odd_frame ^= 1;
139  return pkt->size;
140  }
141  ret = av_new_packet(&yop->video_packet,
142  yop->frame_size - yop->audio_block_length);
143  if (ret < 0)
144  return ret;
145 
146  yop->video_packet.pos = avio_tell(pb);
147 
148  ret = avio_read(pb, yop->video_packet.data, yop->palette_size);
149  if (ret < 0) {
150  goto err_out;
151  }else if (ret < yop->palette_size) {
152  ret = AVERROR_EOF;
153  goto err_out;
154  }
155 
156  ret = av_get_packet(pb, pkt, 920);
157  if (ret < 0)
158  goto err_out;
159 
160  // Set position to the start of the frame
161  pkt->pos = yop->video_packet.pos;
162 
163  avio_skip(pb, yop->audio_block_length - ret);
164 
165  ret = avio_read(pb, yop->video_packet.data + yop->palette_size,
166  actual_video_data_size);
167  if (ret < 0)
168  goto err_out;
169  else if (ret < actual_video_data_size)
170  av_shrink_packet(&yop->video_packet, yop->palette_size + ret);
171 
172  // Arbitrarily return the audio data first
173  return yop->audio_block_length;
174 
175 err_out:
177  return ret;
178 }
179 
181 {
182  YopDecContext *yop = s->priv_data;
184  return 0;
185 }
186 
187 static int yop_read_seek(AVFormatContext *s, int stream_index,
188  int64_t timestamp, int flags)
189 {
190  YopDecContext *yop = s->priv_data;
191  int64_t frame_pos, pos_min, pos_max;
192  int frame_count;
193 
194  if (!stream_index)
195  return -1;
196 
197  pos_min = s->internal->data_offset;
198  pos_max = avio_size(s->pb) - yop->frame_size;
199  frame_count = (pos_max - pos_min) / yop->frame_size;
200 
201  timestamp = FFMAX(0, FFMIN(frame_count, timestamp));
202 
203  frame_pos = timestamp * yop->frame_size + pos_min;
204 
205  if (avio_seek(s->pb, frame_pos, SEEK_SET) < 0)
206  return -1;
207 
209  yop->odd_frame = timestamp & 1;
210 
211  return 0;
212 }
213 
215  .name = "yop",
216  .long_name = NULL_IF_CONFIG_SMALL("Psygnosis YOP"),
217  .priv_data_size = sizeof(YopDecContext),
223  .extensions = "yop",
225 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
Bytestream IO Context.
Definition: avio.h:147
#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:309
static int yop_read_header(AVFormatContext *s)
Definition: yop.c:56
static int yop_read_close(AVFormatContext *s)
Definition: yop.c:180
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1620
void av_shrink_packet(AVPacket *pkt, int size)
Reduce packet size, correctly zeroing padding.
Definition: avpacket.c:101
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:4549
int64_t data_offset
offset of the first packet
Definition: internal.h:82
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: avcodec.h:3979
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition: avformat.h:948
int size
Definition: avcodec.h:1601
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:230
AVFormatInternal * internal
An opaque field for libavformat internal usage.
Definition: avformat.h:1759
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:304
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: avcodec.h:3971
Format I/O context.
Definition: avformat.h:1330
int width
Video only.
Definition: avcodec.h:4045
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:4182
uint8_t * data
Definition: avcodec.h:1600
#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:289
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:511
uint64_t channel_layout
Audio only.
Definition: avcodec.h:4081
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:604
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: avcodec.h:4008
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1632
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
#define AVERROR(e)
Definition: error.h:43
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:176
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3975
AVBufferRef * buf
A reference to the reference-counted buffer where the packet data is stored.
Definition: avcodec.h:1583
#define FFMAX(a, b)
Definition: common.h:94
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1606
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:595
static int yop_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: yop.c:120
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:463
static int yop_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: yop.c:187
int audio_block_length
Definition: yop.c:35
int frame_size
Definition: yop.c:34
audio channel layout utility functions
int ff_alloc_extradata(AVCodecParameters *par, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0...
Definition: utils.c:3165
#define FFMIN(a, b)
Definition: common.h:96
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
AVInputFormat ff_yop_demuxer
Definition: yop.c:214
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:514
Stream structure.
Definition: avformat.h:881
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:1372
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:567
static int yop_probe(AVProbeData *probe_packet)
Definition: yop.c:39
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:487
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:461
static int flags
Definition: cpu.c:47
int sample_rate
Audio only.
Definition: avcodec.h:4089
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:473
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:710
Main libavformat public API header.
void * priv_data
Format private data.
Definition: avformat.h:1358
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: avcodec.h:3993
int channels
Audio only.
Definition: avcodec.h:4085
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:662
AVCodecParameters * codecpar
Definition: avformat.h:1233
int odd_frame
Definition: yop.c:33
int stream_index
Definition: avcodec.h:1602
#define AV_CH_LAYOUT_MONO
This structure stores compressed data.
Definition: avcodec.h:1577