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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(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 (pes_signal != 1 || pes_header_data_length == 0) {
138  pva_log(s, AV_LOG_WARNING, "expected non empty signaled PES packet, "
139  "trying to recover\n");
140  avio_skip(pb, length - 9);
141  if (!read_packet)
142  return AVERROR(EIO);
143  goto recover;
144  }
145 
146  ret = avio_read(pb, pes_header_data, pes_header_data_length);
147  if (ret != pes_header_data_length)
148  return ret < 0 ? ret : AVERROR_INVALIDDATA;
149  length -= 9 + pes_header_data_length;
150 
151  pes_packet_length -= 3 + pes_header_data_length;
152 
153  pvactx->continue_pes = pes_packet_length;
154 
155  if (pes_flags & 0x80 && (pes_header_data[0] & 0xf0) == 0x20) {
156  if (pes_header_data_length < 5) {
157  pva_log(s, AV_LOG_ERROR, "header too short\n");
158  avio_skip(pb, length);
159  return AVERROR_INVALIDDATA;
160  }
161  pva_pts = ff_parse_pes_pts(pes_header_data);
162  }
163  }
164 
165  pvactx->continue_pes -= length;
166 
167  if (pvactx->continue_pes < 0) {
168  pva_log(s, AV_LOG_WARNING, "audio data corruption\n");
169  pvactx->continue_pes = 0;
170  }
171  }
172 
173  if (pva_pts != AV_NOPTS_VALUE)
174  av_add_index_entry(s->streams[streamid-1], startpos, pva_pts, 0, 0, AVINDEX_KEYFRAME);
175 
176  *pts = pva_pts;
177  *len = length;
178  *strid = streamid;
179  return 0;
180 }
181 
183  AVIOContext *pb = s->pb;
184  int64_t pva_pts;
185  int ret, length, streamid;
186 
187  if (read_part_of_packet(s, &pva_pts, &length, &streamid, 1) < 0 ||
188  (ret = av_get_packet(pb, pkt, length)) <= 0)
189  return AVERROR(EIO);
190 
191  pkt->stream_index = streamid - 1;
192  pkt->pts = pva_pts;
193 
194  return ret;
195 }
196 
197 static int64_t pva_read_timestamp(struct AVFormatContext *s, int stream_index,
198  int64_t *pos, int64_t pos_limit) {
199  AVIOContext *pb = s->pb;
200  PVAContext *pvactx = s->priv_data;
201  int length, streamid;
202  int64_t res = AV_NOPTS_VALUE;
203 
204  pos_limit = FFMIN(*pos+PVA_MAX_PAYLOAD_LENGTH*8, (uint64_t)*pos+pos_limit);
205 
206  while (*pos < pos_limit) {
207  res = AV_NOPTS_VALUE;
208  avio_seek(pb, *pos, SEEK_SET);
209 
210  pvactx->continue_pes = 0;
211  if (read_part_of_packet(s, &res, &length, &streamid, 0)) {
212  (*pos)++;
213  continue;
214  }
215  if (streamid - 1 != stream_index || res == AV_NOPTS_VALUE) {
216  *pos = avio_tell(pb) + length;
217  continue;
218  }
219  break;
220  }
221 
222  pvactx->continue_pes = 0;
223  return res;
224 }
225 
227  .name = "pva",
228  .long_name = NULL_IF_CONFIG_SMALL("TechnoTrend PVA"),
229  .priv_data_size = sizeof(PVAContext),
233  .read_timestamp = pva_read_timestamp,
234 };
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:182
const char * s
Definition: avisynth_c.h:631
Bytestream IO Context.
Definition: avio.h:111
#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:1897
#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:4399
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:3911
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:213
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:287
static AVPacket pkt
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:688
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:1319
#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:703
enum AVStreamParseType need_parsing
Definition: avformat.h:1074
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4037
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1387
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:260
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:447
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:550
#define AVINDEX_KEYFRAME
Definition: avformat.h:823
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AVERROR(e)
Definition: error.h:43
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:176
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3907
GLsizei GLsizei * length
Definition: opengl_enc.c:115
Definition: pva.c:31
static int64_t ff_parse_pes_pts(const uint8_t *buf)
Parse MPEG-PES five-byte timestamp.
Definition: mpeg.h:67
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:541
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:462
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:461
#define PVA_AUDIO_PAYLOAD
Definition: pva.c:28
unsigned int avio_rb24(AVIOContext *s)
Definition: aviobuf.c:696
static int64_t pva_read_timestamp(struct AVFormatContext *s, int stream_index, int64_t *pos, int64_t pos_limit)
Definition: pva.c:197
#define FFMIN(a, b)
Definition: common.h:96
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
AVInputFormat ff_pva_demuxer
Definition: pva.c:226
preferred ID for MPEG-1/2 video decoding
Definition: avcodec.h:194
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:638
#define PVA_MAX_PAYLOAD_LENGTH
Definition: pva.c:26
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:1361
void * buf
Definition: avisynth_c.h:553
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:469
This structure contains the data a format has to probe a file.
Definition: avformat.h:459
static int64_t pts
Global timestamp for the audio frames.
static int flags
Definition: cpu.c:47
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:471
full parsing and repack
Definition: avformat.h:806
Main libavformat public API header.
#define pva_log
Definition: pva.c:80
static int pva_probe(AVProbeData *pd)
Definition: pva.c:43
int len
void * priv_data
Format private data.
Definition: avformat.h:1347
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:660
AVCodecParameters * codecpar
Definition: avformat.h:1006
int stream_index
Definition: avcodec.h:1576
This structure stores compressed data.
Definition: avcodec.h:1551
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1567
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:240