FFmpeg
dtshddec.c
Go to the documentation of this file.
1 /*
2  * Raw DTS-HD demuxer
3  * Copyright (c) 2012 Paul B Mahol
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 "libavutil/intreadwrite.h"
23 #include "libavutil/dict.h"
24 #include "libavcodec/dca.h"
25 #include "avformat.h"
26 #include "internal.h"
27 
28 #define AUPR_HDR 0x415550522D484452
29 #define AUPRINFO 0x41555052494E464F
30 #define BITSHVTB 0x4249545348565442
31 #define BLACKOUT 0x424C41434B4F5554
32 #define BRANCHPT 0x4252414E43485054
33 #define BUILDVER 0x4255494C44564552
34 #define CORESSMD 0x434F524553534D44
35 #define DTSHDHDR 0x4454534844484452
36 #define EXTSS_MD 0x45585453535f4d44
37 #define FILEINFO 0x46494C45494E464F
38 #define NAVI_TBL 0x4E4156492D54424C
39 #define STRMDATA 0x5354524D44415441
40 #define TIMECODE 0x54494D45434F4445
41 
42 typedef struct DTSHDDemuxContext {
43  uint64_t data_end;
45 
46 static int dtshd_probe(const AVProbeData *p)
47 {
48  if (AV_RB64(p->buf) == DTSHDHDR)
49  return AVPROBE_SCORE_MAX;
50  return 0;
51 }
52 
54 {
55  DTSHDDemuxContext *dtshd = s->priv_data;
56  AVIOContext *pb = s->pb;
57  uint64_t chunk_type, chunk_size;
58  int64_t duration, orig_nb_samples, data_start;
59  AVStream *st;
60  int ret;
61  char *value;
62 
63  st = avformat_new_stream(s, NULL);
64  if (!st)
65  return AVERROR(ENOMEM);
69 
70  for (;;) {
71  chunk_type = avio_rb64(pb);
72  chunk_size = avio_rb64(pb);
73 
74  if (avio_feof(pb))
75  break;
76 
77  if (chunk_size < 4) {
78  av_log(s, AV_LOG_ERROR, "chunk size too small\n");
79  return AVERROR_INVALIDDATA;
80  }
81  if (chunk_size > ((uint64_t)1 << 61)) {
82  av_log(s, AV_LOG_ERROR, "chunk size too big\n");
83  return AVERROR_INVALIDDATA;
84  }
85 
86  switch (chunk_type) {
87  case STRMDATA:
88  data_start = avio_tell(pb);
89  dtshd->data_end = data_start + chunk_size;
90  if (dtshd->data_end <= chunk_size)
91  return AVERROR_INVALIDDATA;
92  if (!(pb->seekable & AVIO_SEEKABLE_NORMAL))
93  goto break_loop;
94  goto skip;
95  break;
96  case AUPR_HDR:
97  if (chunk_size < 21)
98  return AVERROR_INVALIDDATA;
99  avio_skip(pb, 3);
100  st->codecpar->sample_rate = avio_rb24(pb);
101  if (!st->codecpar->sample_rate)
102  return AVERROR_INVALIDDATA;
103  duration = avio_rb32(pb); // num_frames
104  duration *= avio_rb16(pb); // samples_per_frames
105  st->duration = duration;
106  orig_nb_samples = avio_rb32(pb);
107  orig_nb_samples <<= 8;
108  orig_nb_samples |= avio_r8(pb);
111  st->codecpar->trailing_padding = FFMAX(st->duration - orig_nb_samples - st->codecpar->initial_padding, 0);
112  avio_skip(pb, chunk_size - 21);
113  break;
114  case FILEINFO:
115  if (chunk_size > INT_MAX)
116  goto skip;
117  value = av_malloc(chunk_size);
118  if (!value)
119  goto skip;
120  avio_read(pb, value, chunk_size);
121  value[chunk_size - 1] = 0;
122  av_dict_set(&s->metadata, "fileinfo", value,
124  break;
125  default:
126 skip:
127  ret = avio_skip(pb, chunk_size);
128  if (ret < 0)
129  return ret;
130  };
131  }
132 
133  if (!dtshd->data_end)
134  return AVERROR_EOF;
135 
136  avio_seek(pb, data_start, SEEK_SET);
137 
138 break_loop:
139  if (st->codecpar->sample_rate)
140  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
141 
142  return 0;
143 }
144 
146 {
147  DTSHDDemuxContext *dtshd = s->priv_data;
148  int64_t size, left;
149  int ret;
150 
151  left = dtshd->data_end - avio_tell(s->pb);
152  size = FFMIN(left, 1024);
153  if (size <= 0)
154  return AVERROR_EOF;
155 
156  ret = av_get_packet(s->pb, pkt, size);
157  if (ret < 0)
158  return ret;
159 
160  pkt->stream_index = 0;
161 
162  return ret;
163 }
164 
166  .name = "dtshd",
167  .long_name = NULL_IF_CONFIG_SMALL("raw DTS-HD"),
168  .priv_data_size = sizeof(DTSHDDemuxContext),
173  .extensions = "dtshd",
174  .raw_codec_id = AV_CODEC_ID_DTS,
175 };
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
dca.h
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
raw_read_packet
static int raw_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dtshddec.c:145
DTSHDHDR
#define DTSHDHDR
Definition: dtshddec.c:35
FFMAX
#define FFMAX(a, b)
Definition: macros.h:47
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:311
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:30
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
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:413
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
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:897
AV_DICT_DONT_STRDUP_VAL
#define AV_DICT_DONT_STRDUP_VAL
Take ownership of a value that's been allocated with av_malloc() or another memory allocation functio...
Definition: dict.h:79
DTSHDDemuxContext::data_end
uint64_t data_end
Definition: dtshddec.c:43
avio_rb32
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:782
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
duration
int64_t duration
Definition: movenc.c:64
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:41
dtshd_probe
static int dtshd_probe(const AVProbeData *p)
Definition: dtshddec.c:46
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:256
FILEINFO
#define FILEINFO
Definition: dtshddec.c:37
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
AUPR_HDR
#define AUPR_HDR
Definition: dtshddec.c:28
FFStream::need_parsing
enum AVStreamParseType need_parsing
Definition: internal.h:386
AVFormatContext
Format I/O context.
Definition: avformat.h:1104
ff_dtshd_demuxer
const AVInputFormat ff_dtshd_demuxer
Definition: dtshddec.c:165
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
avio_rb64
uint64_t avio_rb64(AVIOContext *s)
Definition: aviobuf.c:929
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
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:178
AVIOContext
Bytestream IO Context.
Definition: avio.h:166
avio_rb24
unsigned int avio_rb24(AVIOContext *s)
Definition: aviobuf.c:775
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
AVIOContext::seekable
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:267
AV_CODEC_ID_DTS
@ AV_CODEC_ID_DTS
Definition: codec_id.h:442
size
int size
Definition: twinvq_data.h:10344
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:624
STRMDATA
#define STRMDATA
Definition: dtshddec.c:39
value
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default value
Definition: writing_filters.txt:86
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
dtshd_read_header
static int dtshd_read_header(AVFormatContext *s)
Definition: dtshddec.c:53
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
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
avio_rb16
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:767
avformat.h
dict.h
left
Tag MUST be and< 10hcoeff half pel interpolation filter coefficients, hcoeff[0] are the 2 middle coefficients[1] are the next outer ones and so on, resulting in a filter like:...eff[2], hcoeff[1], hcoeff[0], hcoeff[0], hcoeff[1], hcoeff[2] ... the sign of the coefficients is not explicitly stored but alternates after each coeff and coeff[0] is positive, so ...,+,-,+,-,+,+,-,+,-,+,... hcoeff[0] is not explicitly stored but found by subtracting the sum of all stored coefficients with signs from 32 hcoeff[0]=32 - hcoeff[1] - hcoeff[2] - ... a good choice for hcoeff and htaps is htaps=6 hcoeff={40,-10, 2} an alternative which requires more computations at both encoder and decoder side and may or may not be better is htaps=8 hcoeff={42,-14, 6,-2}ref_frames minimum of the number of available reference frames and max_ref_frames for example the first frame after a key frame always has ref_frames=1spatial_decomposition_type wavelet type 0 is a 9/7 symmetric compact integer wavelet 1 is a 5/3 symmetric compact integer wavelet others are reserved stored as delta from last, last is reset to 0 if always_reset||keyframeqlog quality(logarithmic quantizer scale) stored as delta from last, last is reset to 0 if always_reset||keyframemv_scale stored as delta from last, last is reset to 0 if always_reset||keyframe FIXME check that everything works fine if this changes between framesqbias dequantization bias stored as delta from last, last is reset to 0 if always_reset||keyframeblock_max_depth maximum depth of the block tree stored as delta from last, last is reset to 0 if always_reset||keyframequant_table quantization tableHighlevel bitstream structure:==============================--------------------------------------------|Header|--------------------------------------------|------------------------------------|||Block0||||split?||||yes no||||......... intra?||||:Block01 :yes no||||:Block02 :....... ..........||||:Block03 ::y DC ::ref index:||||:Block04 ::cb DC ::motion x :||||......... :cr DC ::motion y :||||....... ..........|||------------------------------------||------------------------------------|||Block1|||...|--------------------------------------------|------------ ------------ ------------|||Y subbands||Cb subbands||Cr subbands||||--- ---||--- ---||--- ---|||||LL0||HL0||||LL0||HL0||||LL0||HL0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||LH0||HH0||||LH0||HH0||||LH0||HH0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HL1||LH1||||HL1||LH1||||HL1||LH1|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HH1||HL2||||HH1||HL2||||HH1||HL2|||||...||...||...|||------------ ------------ ------------|--------------------------------------------Decoding process:=================------------|||Subbands|------------||||------------|Intra DC||||LL0 subband prediction ------------|\ Dequantization ------------------- \||Reference frames|\ IDWT|------- -------|Motion \|||Frame 0||Frame 1||Compensation . OBMC v -------|------- -------|--------------. \------> Frame n output Frame Frame<----------------------------------/|...|------------------- Range Coder:============Binary Range Coder:------------------- The implemented range coder is an adapted version based upon "Range encoding: an algorithm for removing redundancy from a digitised message." by G. N. N. Martin. The symbols encoded by the Snow range coder are bits(0|1). The associated probabilities are not fix but change depending on the symbol mix seen so far. bit seen|new state ---------+----------------------------------------------- 0|256 - state_transition_table[256 - old_state];1|state_transition_table[old_state];state_transition_table={ 0, 0, 0, 0, 0, 0, 0, 0, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 190, 191, 192, 194, 194, 195, 196, 197, 198, 199, 200, 201, 202, 202, 204, 205, 206, 207, 208, 209, 209, 210, 211, 212, 213, 215, 215, 216, 217, 218, 219, 220, 220, 222, 223, 224, 225, 226, 227, 227, 229, 229, 230, 231, 232, 234, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 248, 0, 0, 0, 0, 0, 0, 0};FIXME Range Coding of integers:------------------------- FIXME Neighboring Blocks:===================left and top are set to the respective blocks unless they are outside of the image in which case they are set to the Null block top-left is set to the top left block unless it is outside of the image in which case it is set to the left block if this block has no larger parent block or it is at the left side of its parent block and the top right block is not outside of the image then the top right block is used for top-right else the top-left block is used Null block y, cb, cr are 128 level, ref, mx and my are 0 Motion Vector Prediction:=========================1. the motion vectors of all the neighboring blocks are scaled to compensate for the difference of reference frames scaled_mv=(mv *(256 *(current_reference+1)/(mv.reference+1))+128)> the median of the scaled left
Definition: snow.txt:386
AVCodecParameters::trailing_padding
int trailing_padding
Audio only.
Definition: codec_par.h:204
AVIO_SEEKABLE_NORMAL
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:41
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:633
AVSTREAM_PARSE_FULL_RAW
@ AVSTREAM_PARSE_FULL_RAW
full parsing and repack with timestamp and position generation by parser for raw this assumes that ea...
Definition: avformat.h:692
AVPacket::stream_index
int stream_index
Definition: packet.h:376
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:339
DTSHDDemuxContext
Definition: dtshddec.c:42
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:29
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
av_dict_set
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:86
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
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
AVCodecParameters::initial_padding
int initial_padding
Audio only.
Definition: codec_par.h:197
skip
static void BS_FUNC() skip(BSCTX *bc, unsigned int n)
Skip n bits in the buffer.
Definition: bitstream_template.h:375
AV_RB64
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_RB64
Definition: bytestream.h:95
ff_dca_count_chs_for_mask
static int ff_dca_count_chs_for_mask(unsigned int mask)
Return number of individual channels in DCASpeakerPair mask.
Definition: dca.h:158
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:367