FFmpeg
ttaenc.c
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1 /*
2  * TTA (The Lossless True Audio) encoder
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #define BITSTREAM_WRITER_LE
22 #include "ttadata.h"
23 #include "ttaencdsp.h"
24 #include "avcodec.h"
25 #include "codec_internal.h"
26 #include "encode.h"
27 #include "put_bits.h"
28 #include "libavutil/crc.h"
29 
30 typedef struct TTAEncContext {
31  const AVCRC *crc_table;
32  int bps;
36 
38 {
39  TTAEncContext *s = avctx->priv_data;
40 
41  s->crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE);
42 
43  switch (avctx->sample_fmt) {
44  case AV_SAMPLE_FMT_U8:
45  avctx->bits_per_raw_sample = 8;
46  break;
47  case AV_SAMPLE_FMT_S16:
48  avctx->bits_per_raw_sample = 16;
49  break;
50  case AV_SAMPLE_FMT_S32:
51  if (avctx->bits_per_raw_sample > 24)
52  av_log(avctx, AV_LOG_WARNING, "encoding as 24 bits-per-sample\n");
53  avctx->bits_per_raw_sample = 24;
54  }
55 
56  s->bps = avctx->bits_per_raw_sample >> 3;
57  avctx->frame_size = 256 * avctx->sample_rate / 245;
58 
59  s->ch_ctx = av_malloc_array(avctx->ch_layout.nb_channels, sizeof(*s->ch_ctx));
60  if (!s->ch_ctx)
61  return AVERROR(ENOMEM);
62 
63  ff_ttaencdsp_init(&s->dsp);
64 
65  return 0;
66 }
67 
68 static int32_t get_sample(const AVFrame *frame, int sample,
70 {
71  int32_t ret;
72 
73  if (format == AV_SAMPLE_FMT_U8) {
74  ret = frame->data[0][sample] - 0x80;
75  } else if (format == AV_SAMPLE_FMT_S16) {
76  const int16_t *ptr = (const int16_t *)frame->data[0];
77  ret = ptr[sample];
78  } else {
79  const int32_t *ptr = (const int32_t *)frame->data[0];
80  ret = ptr[sample] >> 8;
81  }
82 
83  return ret;
84 }
85 
86 static int tta_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
87  const AVFrame *frame, int *got_packet_ptr)
88 {
89  TTAEncContext *s = avctx->priv_data;
90  PutBitContext pb;
91  int ret, i, out_bytes, cur_chan, res, samples;
92  int64_t pkt_size = frame->nb_samples * 2LL * avctx->ch_layout.nb_channels * s->bps;
93 
94 pkt_alloc:
95  cur_chan = 0, res = 0, samples = 0;
96  if ((ret = ff_alloc_packet(avctx, avpkt, pkt_size)) < 0)
97  return ret;
98  init_put_bits(&pb, avpkt->data, avpkt->size);
99 
100  // init per channel states
101  for (i = 0; i < avctx->ch_layout.nb_channels; i++) {
102  s->ch_ctx[i].predictor = 0;
103  ff_tta_filter_init(&s->ch_ctx[i].filter, ff_tta_filter_configs[s->bps - 1]);
104  ff_tta_rice_init(&s->ch_ctx[i].rice, 10, 10);
105  }
106 
107  for (i = 0; i < frame->nb_samples * avctx->ch_layout.nb_channels; i++) {
108  TTAChannel *c = &s->ch_ctx[cur_chan];
109  TTAFilter *filter = &c->filter;
110  TTARice *rice = &c->rice;
111  uint32_t k, unary, outval;
112  int32_t value, temp;
113 
114  value = get_sample(frame, samples++, avctx->sample_fmt);
115 
116  if (avctx->ch_layout.nb_channels > 1) {
117  if (cur_chan < avctx->ch_layout.nb_channels - 1)
118  value = res = get_sample(frame, samples, avctx->sample_fmt) - value;
119  else
120  value -= res / 2;
121  }
122 
123  temp = value;
124 #define PRED(x, k) (int32_t)((((uint64_t)(x) << (k)) - (x)) >> (k))
125  switch (s->bps) {
126  case 1: value -= PRED(c->predictor, 4); break;
127  case 2:
128  case 3: value -= PRED(c->predictor, 5); break;
129  }
130  c->predictor = temp;
131 
132  s->dsp.filter_process(filter->qm, filter->dx, filter->dl, &filter->error, &value,
133  filter->shift, filter->round);
134  outval = (value > 0) ? (value << 1) - 1: -value << 1;
135 
136  k = rice->k0;
137 
138  rice->sum0 += outval - (rice->sum0 >> 4);
139  if (rice->k0 > 0 && rice->sum0 < ff_tta_shift_16[rice->k0])
140  rice->k0--;
141  else if (rice->sum0 > ff_tta_shift_16[rice->k0 + 1])
142  rice->k0++;
143 
144  if (outval >= ff_tta_shift_1[k]) {
145  outval -= ff_tta_shift_1[k];
146  k = rice->k1;
147 
148  rice->sum1 += outval - (rice->sum1 >> 4);
149  if (rice->k1 > 0 && rice->sum1 < ff_tta_shift_16[rice->k1])
150  rice->k1--;
151  else if (rice->sum1 > ff_tta_shift_16[rice->k1 + 1])
152  rice->k1++;
153 
154  unary = 1 + (outval >> k);
155  if (unary + 100LL > put_bits_left(&pb)) {
156  if (pkt_size < INT_MAX/2) {
157  pkt_size *= 2;
158  av_packet_unref(avpkt);
159  goto pkt_alloc;
160  } else
161  return AVERROR(ENOMEM);
162  }
163  do {
164  if (unary > 31) {
165  put_bits(&pb, 31, 0x7FFFFFFF);
166  unary -= 31;
167  } else {
168  put_bits(&pb, unary, (1U << unary) - 1);
169  unary = 0;
170  }
171  } while (unary);
172  }
173 
174  put_bits(&pb, 1, 0);
175 
176  if (k)
177  put_bits(&pb, k, outval & (ff_tta_shift_1[k] - 1));
178 
179  if (cur_chan < avctx->ch_layout.nb_channels - 1)
180  cur_chan++;
181  else
182  cur_chan = 0;
183  }
184 
185  flush_put_bits(&pb);
186  out_bytes = put_bytes_output(&pb);
187  put_bits32(&pb, av_crc(s->crc_table, UINT32_MAX, avpkt->data, out_bytes) ^ UINT32_MAX);
188  flush_put_bits(&pb);
189 
190  avpkt->size = out_bytes + 4;
191  *got_packet_ptr = 1;
192  return 0;
193 }
194 
196 {
197  TTAEncContext *s = avctx->priv_data;
198  av_freep(&s->ch_ctx);
199  return 0;
200 }
201 
203  .p.name = "tta",
204  CODEC_LONG_NAME("TTA (True Audio)"),
205  .p.type = AVMEDIA_TYPE_AUDIO,
206  .p.id = AV_CODEC_ID_TTA,
207  .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_SMALL_LAST_FRAME |
209  .priv_data_size = sizeof(TTAEncContext),
211  .close = tta_encode_close,
213  .p.sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_U8,
217 };
AVCodecContext::frame_size
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:1096
av_packet_unref
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:427
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
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
tta_encode_frame
static int tta_encode_frame(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
Definition: ttaenc.c:86
put_bits32
static void av_unused put_bits32(PutBitContext *s, uint32_t value)
Write exactly 32 bits into a bitstream.
Definition: put_bits.h:291
put_bytes_output
static int put_bytes_output(const PutBitContext *s)
Definition: put_bits.h:89
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:1068
AVCRC
uint32_t AVCRC
Definition: crc.h:46
init_put_bits
static void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
Initialize the PutBitContext s.
Definition: put_bits.h:62
ff_tta_filter_init
void ff_tta_filter_init(TTAFilter *c, int32_t shift)
Definition: ttadata.c:50
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
put_bits
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:222
AVPacket::data
uint8_t * data
Definition: packet.h:522
encode.h
FFCodec
Definition: codec_internal.h:127
ff_ttaencdsp_init
av_cold void ff_ttaencdsp_init(TTAEncDSPContext *c)
Definition: ttaencdsp.c:53
filter
filter_frame For filters that do not use the this method is called when a frame is pushed to the filter s input It can be called at any time except in a reentrant way If the input frame is enough to produce then the filter should push the output frames on the output link immediately As an exception to the previous rule if the input frame is enough to produce several output frames then the filter needs output only at least one per link The additional frames can be left buffered in the filter
Definition: filter_design.txt:228
ff_tta_rice_init
void ff_tta_rice_init(TTARice *c, uint32_t k0, uint32_t k1)
Definition: ttadata.c:42
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:323
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:361
TTARice::k1
uint32_t k1
Definition: ttadata.h:35
crc.h
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
AVCodecContext::ch_layout
AVChannelLayout ch_layout
Audio channel layout.
Definition: avcodec.h:2111
put_bits_left
static int put_bits_left(PutBitContext *s)
Definition: put_bits.h:125
TTARice::sum1
uint32_t sum1
Definition: ttadata.h:35
FF_CODEC_ENCODE_CB
#define FF_CODEC_ENCODE_CB(func)
Definition: codec_internal.h:315
av_cold
#define av_cold
Definition: attributes.h:90
tta_encode_close
static av_cold int tta_encode_close(AVCodecContext *avctx)
Definition: ttaenc.c:195
AV_CODEC_ID_TTA
@ AV_CODEC_ID_TTA
Definition: codec_id.h:465
TTAEncContext::ch_ctx
TTAChannel * ch_ctx
Definition: ttaenc.c:33
s
#define s(width, name)
Definition: cbs_vp9.c:198
format
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 format(the sample packing is implied by the sample format) and sample rate. The lists are not just lists
TTAEncContext::dsp
TTAEncDSPContext dsp
Definition: ttaenc.c:34
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE
#define AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE
This encoder can reorder user opaque values from input AVFrames and return them with corresponding ou...
Definition: codec.h:159
AVCodecContext::bits_per_raw_sample
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:1521
TTAEncContext::bps
int bps
Definition: ttaenc.c:32
PutBitContext
Definition: put_bits.h:50
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:272
frame
static AVFrame * frame
Definition: demux_decode.c:54
TTARice::sum0
uint32_t sum0
Definition: ttadata.h:35
TTAFilter
Definition: ttadata.h:27
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
init
int(* init)(AVBSFContext *ctx)
Definition: dts2pts.c:365
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
AVPacket::size
int size
Definition: packet.h:523
codec_internal.h
PRED
#define PRED(x, k)
AVCodecContext::sample_fmt
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1084
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:56
sample
#define sample
Definition: flacdsp_template.c:44
av_crc_get_table
const AVCRC * av_crc_get_table(AVCRCId crc_id)
Get an initialized standard CRC table.
Definition: crc.c:374
TTAEncContext::crc_table
const AVCRC * crc_table
Definition: ttaenc.c:31
ff_tta_shift_1
const uint32_t ff_tta_shift_1[]
Definition: ttadata.c:24
AVFrame::nb_samples
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:420
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
AV_SAMPLE_FMT_U8
@ AV_SAMPLE_FMT_U8
unsigned 8 bits
Definition: samplefmt.h:57
ff_tta_shift_16
const uint32_t *const ff_tta_shift_16
Definition: ttadata.c:38
ff_tta_filter_configs
const uint8_t ff_tta_filter_configs[]
Definition: ttadata.c:40
av_malloc_array
#define av_malloc_array(a, b)
Definition: tableprint_vlc.h:31
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:55
ttadata.h
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
AV_SAMPLE_FMT_S16
@ AV_SAMPLE_FMT_S16
signed 16 bits
Definition: samplefmt.h:58
TTAChannel
Definition: ttadata.h:38
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
avcodec.h
TTARice::k0
uint32_t k0
Definition: ttadata.h:35
ret
ret
Definition: filter_design.txt:187
TTARice
Definition: ttadata.h:34
U
#define U(x)
Definition: vpx_arith.h:37
AVCodecContext
main external API structure.
Definition: avcodec.h:445
av_crc
uint32_t av_crc(const AVCRC *ctx, uint32_t crc, const uint8_t *buffer, size_t length)
Calculate the CRC of a block.
Definition: crc.c:392
temp
else temp
Definition: vf_mcdeint.c:263
samples
Filter the word “frame” indicates either a video frame or a group of audio samples
Definition: filter_design.txt:8
ff_tta_encoder
const FFCodec ff_tta_encoder
Definition: ttaenc.c:202
AV_CRC_32_IEEE_LE
@ AV_CRC_32_IEEE_LE
Definition: crc.h:53
TTAEncDSPContext
Definition: ttaencdsp.h:24
flush_put_bits
static void flush_put_bits(PutBitContext *s)
Pad the end of the output stream with zeros.
Definition: put_bits.h:143
AVPacket
This structure stores compressed data.
Definition: packet.h:499
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:472
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
TTAEncContext
Definition: ttaenc.c:30
int32_t
int32_t
Definition: audioconvert.c:56
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
get_sample
static int32_t get_sample(const AVFrame *frame, int sample, enum AVSampleFormat format)
Definition: ttaenc.c:68
ttaencdsp.h
AV_CODEC_CAP_SMALL_LAST_FRAME
#define AV_CODEC_CAP_SMALL_LAST_FRAME
Codec can be fed a final frame with a smaller size.
Definition: codec.h:81
put_bits.h
AV_SAMPLE_FMT_S32
@ AV_SAMPLE_FMT_S32
signed 32 bits
Definition: samplefmt.h:59
ff_alloc_packet
int ff_alloc_packet(AVCodecContext *avctx, AVPacket *avpkt, int64_t size)
Check AVPacket size and allocate data.
Definition: encode.c:61
tta_encode_init
static av_cold int tta_encode_init(AVCodecContext *avctx)
Definition: ttaenc.c:37