FFmpeg
pva.c
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1 /*
2  * TechnoTrend PVA (.pva) demuxer
3  * Copyright (c) 2007, 2008 Ivo van Poorten
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 "internal.h"
24 #include "mpeg.h"
25 
26 #define PVA_MAX_PAYLOAD_LENGTH 0x17f8
27 #define PVA_VIDEO_PAYLOAD 0x01
28 #define PVA_AUDIO_PAYLOAD 0x02
29 #define PVA_MAGIC (('A' << 8) + 'V')
30 
31 typedef struct PVAContext {
33 } PVAContext;
34 
35 static int pva_check(const uint8_t *p) {
36  int length = AV_RB16(p + 6);
37  if (AV_RB16(p) != PVA_MAGIC || !p[2] || p[2] > 2 || p[4] != 0x55 ||
38  (p[5] & 0xe0) || length > PVA_MAX_PAYLOAD_LENGTH)
39  return -1;
40  return length + 8;
41 }
42 
43 static int pva_probe(const AVProbeData * pd) {
44  const unsigned char *buf = pd->buf;
45  int len = pva_check(buf);
46 
47  if (len < 0)
48  return 0;
49 
50  if (pd->buf_size >= len + 8 &&
51  pva_check(buf + len) >= 0)
53 
54  return AVPROBE_SCORE_MAX / 4;
55 }
56 
58  AVStream *st;
59 
60  if (!(st = avformat_new_stream(s, NULL)))
61  return AVERROR(ENOMEM);
65  avpriv_set_pts_info(st, 32, 1, 90000);
66  av_add_index_entry(st, 0, 0, 0, 0, AVINDEX_KEYFRAME);
67 
68  if (!(st = avformat_new_stream(s, NULL)))
69  return AVERROR(ENOMEM);
73  avpriv_set_pts_info(st, 33, 1, 90000);
74  av_add_index_entry(st, 0, 0, 0, 0, AVINDEX_KEYFRAME);
75 
76  /* the parameters will be extracted from the compressed bitstream */
77  return 0;
78 }
79 
80 #define pva_log if (read_packet) av_log
81 
82 static int read_part_of_packet(AVFormatContext *s, int64_t *pts,
83  int *len, int *strid, int read_packet) {
84  AVIOContext *pb = s->pb;
85  PVAContext *pvactx = s->priv_data;
86  int syncword, streamid, reserved, flags, length, pts_flag;
87  int64_t pva_pts = AV_NOPTS_VALUE, startpos;
88  int ret;
89 
90 recover:
91  startpos = avio_tell(pb);
92 
93  syncword = avio_rb16(pb);
94  streamid = avio_r8(pb);
95  avio_r8(pb); /* counter not used */
96  reserved = avio_r8(pb);
97  flags = avio_r8(pb);
98  length = avio_rb16(pb);
99 
100  pts_flag = flags & 0x10;
101 
102  if (syncword != PVA_MAGIC) {
103  pva_log(s, AV_LOG_ERROR, "invalid syncword\n");
104  return AVERROR(EIO);
105  }
106  if (streamid != PVA_VIDEO_PAYLOAD && streamid != PVA_AUDIO_PAYLOAD) {
107  pva_log(s, AV_LOG_ERROR, "invalid streamid\n");
108  return AVERROR(EIO);
109  }
110  if (reserved != 0x55) {
111  pva_log(s, AV_LOG_WARNING, "expected reserved byte to be 0x55\n");
112  }
113  if (length > PVA_MAX_PAYLOAD_LENGTH) {
114  pva_log(s, AV_LOG_ERROR, "invalid payload length %u\n", length);
115  return AVERROR(EIO);
116  }
117 
118  if (streamid == PVA_VIDEO_PAYLOAD && pts_flag) {
119  pva_pts = avio_rb32(pb);
120  length -= 4;
121  } else if (streamid == PVA_AUDIO_PAYLOAD) {
122  /* PVA Audio Packets either start with a signaled PES packet or
123  * are a continuation of the previous PES packet. New PES packets
124  * always start at the beginning of a PVA Packet, never somewhere in
125  * the middle. */
126  if (!pvactx->continue_pes) {
127  int pes_signal, pes_header_data_length, pes_packet_length,
128  pes_flags;
129  unsigned char pes_header_data[256];
130 
131  pes_signal = avio_rb24(pb);
132  avio_r8(pb);
133  pes_packet_length = avio_rb16(pb);
134  pes_flags = avio_rb16(pb);
135  pes_header_data_length = avio_r8(pb);
136 
137  if (avio_feof(pb)) {
138  return AVERROR_EOF;
139  }
140 
141  if (pes_signal != 1 || pes_header_data_length == 0) {
142  pva_log(s, AV_LOG_WARNING, "expected non empty signaled PES packet, "
143  "trying to recover\n");
144  avio_skip(pb, length - 9);
145  if (!read_packet)
146  return AVERROR(EIO);
147  goto recover;
148  }
149 
150  ret = avio_read(pb, pes_header_data, pes_header_data_length);
151  if (ret != pes_header_data_length)
152  return ret < 0 ? ret : AVERROR_INVALIDDATA;
153  length -= 9 + pes_header_data_length;
154 
155  pes_packet_length -= 3 + pes_header_data_length;
156 
157  pvactx->continue_pes = pes_packet_length;
158 
159  if (pes_flags & 0x80 && (pes_header_data[0] & 0xf0) == 0x20) {
160  if (pes_header_data_length < 5) {
161  pva_log(s, AV_LOG_ERROR, "header too short\n");
162  avio_skip(pb, length);
163  return AVERROR_INVALIDDATA;
164  }
165  pva_pts = ff_parse_pes_pts(pes_header_data);
166  }
167  }
168 
169  pvactx->continue_pes -= length;
170 
171  if (pvactx->continue_pes < 0) {
172  pva_log(s, AV_LOG_WARNING, "audio data corruption\n");
173  pvactx->continue_pes = 0;
174  }
175  }
176 
177  if (pva_pts != AV_NOPTS_VALUE)
178  av_add_index_entry(s->streams[streamid-1], startpos, pva_pts, 0, 0, AVINDEX_KEYFRAME);
179 
180  *pts = pva_pts;
181  *len = length;
182  *strid = streamid;
183  return 0;
184 }
185 
187  AVIOContext *pb = s->pb;
188  int64_t pva_pts;
189  int ret, length, streamid;
190 
191  if (read_part_of_packet(s, &pva_pts, &length, &streamid, 1) < 0 ||
192  (ret = av_get_packet(pb, pkt, length)) <= 0)
193  return AVERROR(EIO);
194 
195  pkt->stream_index = streamid - 1;
196  pkt->pts = pva_pts;
197 
198  return ret;
199 }
200 
201 static int64_t pva_read_timestamp(struct AVFormatContext *s, int stream_index,
202  int64_t *pos, int64_t pos_limit) {
203  AVIOContext *pb = s->pb;
204  PVAContext *pvactx = s->priv_data;
205  int length, streamid;
206  int64_t res = AV_NOPTS_VALUE;
207 
208  pos_limit = FFMIN(*pos+PVA_MAX_PAYLOAD_LENGTH*8, (uint64_t)*pos+pos_limit);
209 
210  while (*pos < pos_limit) {
211  res = AV_NOPTS_VALUE;
212  avio_seek(pb, *pos, SEEK_SET);
213 
214  pvactx->continue_pes = 0;
215  if (read_part_of_packet(s, &res, &length, &streamid, 0)) {
216  (*pos)++;
217  continue;
218  }
219  if (streamid - 1 != stream_index || res == AV_NOPTS_VALUE) {
220  *pos = avio_tell(pb) + length;
221  continue;
222  }
223  break;
224  }
225 
226  pvactx->continue_pes = 0;
227  return res;
228 }
229 
231  .name = "pva",
232  .long_name = NULL_IF_CONFIG_SMALL("TechnoTrend PVA"),
233  .priv_data_size = sizeof(PVAContext),
237  .read_timestamp = pva_read_timestamp,
238 };
static int recover(WtvContext *wtv, uint64_t broken_pos)
Try to seek over a broken chunk.
Definition: wtvdec.c:760
#define NULL
Definition: coverity.c:32
static int pva_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: pva.c:186
Bytestream IO Context.
Definition: avio.h:161
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp, int size, int distance, int flags)
Add an index entry into a sorted list.
Definition: utils.c:2049
#define PVA_MAGIC
Definition: pva.c:29
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
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:4929
static int pva_read_header(AVFormatContext *s)
Definition: pva.c:57
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3968
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
int continue_pes
Definition: pva.c:32
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:334
static AVPacket pkt
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:788
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
Format I/O context.
Definition: avformat.h:1358
#define PVA_VIDEO_PAYLOAD
Definition: pva.c:27
static int read_part_of_packet(AVFormatContext *s, int64_t *pts, int *len, int *strid, int read_packet)
Definition: pva.c:82
uint8_t
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:803
enum AVStreamParseType need_parsing
Definition: avformat.h:1099
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4502
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1426
#define AVERROR_EOF
End of file.
Definition: error.h:55
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:310
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:650
#define AVINDEX_KEYFRAME
Definition: avformat.h:817
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
static int pva_check(const uint8_t *p)
Definition: pva.c:35
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3964
GLsizei GLsizei * length
Definition: opengl_enc.c:114
Definition: pva.c:31
static int64_t ff_parse_pes_pts(const uint8_t *buf)
Parse MPEG-PES five-byte timestamp.
Definition: mpeg.h:68
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:641
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:449
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
#define PVA_AUDIO_PAYLOAD
Definition: pva.c:28
unsigned int avio_rb24(AVIOContext *s)
Definition: aviobuf.c:796
static int64_t pva_read_timestamp(struct AVFormatContext *s, int stream_index, int64_t *pos, int64_t pos_limit)
Definition: pva.c:201
#define FFMIN(a, b)
Definition: common.h:96
AVInputFormat ff_pva_demuxer
Definition: pva.c:230
#define s(width, name)
Definition: cbs_vp9.c:257
preferred ID for MPEG-1/2 video decoding
Definition: avcodec.h:220
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
#define PVA_MAX_PAYLOAD_LENGTH
Definition: pva.c:26
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:1400
void * buf
Definition: avisynth_c.h:766
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:456
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
static int64_t pts
#define flags(name, subs,...)
Definition: cbs_av1.c:561
static int pva_probe(const AVProbeData *pd)
Definition: pva.c:43
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
full parsing and repack
Definition: avformat.h:800
Main libavformat public API header.
#define pva_log
Definition: pva.c:80
int len
void * priv_data
Format private data.
Definition: avformat.h:1386
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:361
int stream_index
Definition: avcodec.h:1482
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
This structure stores compressed data.
Definition: avcodec.h:1457
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1473
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248