FFmpeg
Data Structures | Macros | Functions
pcm.c File Reference
#include "config.h"
#include "libavutil/attributes.h"
#include "libavutil/float_dsp.h"
#include "libavutil/thread.h"
#include "avcodec.h"
#include "bytestream.h"
#include "encode.h"
#include "internal.h"
#include "mathops.h"
#include "pcm_tablegen.h"

Go to the source code of this file.

Data Structures

struct  PCMDecode
 

Macros

#define INIT_ONCE(id, name)
 
#define ENCODE(type, endian, src, dst, n, shift, offset)
 Write PCM samples macro. More...
 
#define ENCODE_PLANAR(type, endian, dst, n, shift, offset)
 
#define DECODE(size, endian, src, dst, n, shift, offset)
 Read PCM samples macro. More...
 
#define DECODE_PLANAR(size, endian, src, dst, n, shift, offset)
 
#define PCM_ENCODER_0(id_, sample_fmt_, name_, long_name_)
 
#define PCM_ENCODER_1(id_, sample_fmt_, name_, long_name_)
 
#define PCM_ENCODER_2(cf, id, sample_fmt, name, long_name)   PCM_ENCODER_ ## cf(id, sample_fmt, name, long_name)
 
#define PCM_ENCODER_3(cf, id, sample_fmt, name, long_name)   PCM_ENCODER_2(cf, id, sample_fmt, name, long_name)
 
#define PCM_ENCODER(id, sample_fmt, name, long_name)   PCM_ENCODER_3(CONFIG_ ## id ## _ENCODER, id, sample_fmt, name, long_name)
 
#define PCM_DECODER_0(id, sample_fmt, name, long_name)
 
#define PCM_DECODER_1(id_, sample_fmt_, name_, long_name_)
 
#define PCM_DECODER_2(cf, id, sample_fmt, name, long_name)   PCM_DECODER_ ## cf(id, sample_fmt, name, long_name)
 
#define PCM_DECODER_3(cf, id, sample_fmt, name, long_name)   PCM_DECODER_2(cf, id, sample_fmt, name, long_name)
 
#define PCM_DECODER(id, sample_fmt, name, long_name)   PCM_DECODER_3(CONFIG_ ## id ## _DECODER, id, sample_fmt, name, long_name)
 
#define PCM_CODEC(id, sample_fmt_, name, long_name_)
 

Functions

static av_cold int pcm_encode_init (AVCodecContext *avctx)
 
static int pcm_encode_frame (AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
 
static av_cold int pcm_decode_init (AVCodecContext *avctx)
 
static int pcm_decode_frame (AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
 
 PCM_CODEC (PCM_ALAW, AV_SAMPLE_FMT_S16, pcm_alaw, "PCM A-law / G.711 A-law")
 
 PCM_DECODER (PCM_F16LE, AV_SAMPLE_FMT_FLT, pcm_f16le, "PCM 16.8 floating point little-endian")
 
 PCM_DECODER (PCM_F24LE, AV_SAMPLE_FMT_FLT, pcm_f24le, "PCM 24.0 floating point little-endian")
 
 PCM_CODEC (PCM_F32BE, AV_SAMPLE_FMT_FLT, pcm_f32be, "PCM 32-bit floating point big-endian")
 
 PCM_CODEC (PCM_F32LE, AV_SAMPLE_FMT_FLT, pcm_f32le, "PCM 32-bit floating point little-endian")
 
 PCM_CODEC (PCM_F64BE, AV_SAMPLE_FMT_DBL, pcm_f64be, "PCM 64-bit floating point big-endian")
 
 PCM_CODEC (PCM_F64LE, AV_SAMPLE_FMT_DBL, pcm_f64le, "PCM 64-bit floating point little-endian")
 
 PCM_DECODER (PCM_LXF, AV_SAMPLE_FMT_S32P, pcm_lxf, "PCM signed 20-bit little-endian planar")
 
 PCM_CODEC (PCM_MULAW, AV_SAMPLE_FMT_S16, pcm_mulaw, "PCM mu-law / G.711 mu-law")
 
 PCM_CODEC (PCM_S8, AV_SAMPLE_FMT_U8, pcm_s8, "PCM signed 8-bit")
 
 PCM_CODEC (PCM_S8_PLANAR, AV_SAMPLE_FMT_U8P, pcm_s8_planar, "PCM signed 8-bit planar")
 
 PCM_CODEC (PCM_S16BE, AV_SAMPLE_FMT_S16, pcm_s16be, "PCM signed 16-bit big-endian")
 
 PCM_CODEC (PCM_S16BE_PLANAR, AV_SAMPLE_FMT_S16P, pcm_s16be_planar, "PCM signed 16-bit big-endian planar")
 
 PCM_CODEC (PCM_S16LE, AV_SAMPLE_FMT_S16, pcm_s16le, "PCM signed 16-bit little-endian")
 
 PCM_CODEC (PCM_S16LE_PLANAR, AV_SAMPLE_FMT_S16P, pcm_s16le_planar, "PCM signed 16-bit little-endian planar")
 
 PCM_CODEC (PCM_S24BE, AV_SAMPLE_FMT_S32, pcm_s24be, "PCM signed 24-bit big-endian")
 
 PCM_CODEC (PCM_S24DAUD, AV_SAMPLE_FMT_S16, pcm_s24daud, "PCM D-Cinema audio signed 24-bit")
 
 PCM_CODEC (PCM_S24LE, AV_SAMPLE_FMT_S32, pcm_s24le, "PCM signed 24-bit little-endian")
 
 PCM_CODEC (PCM_S24LE_PLANAR, AV_SAMPLE_FMT_S32P, pcm_s24le_planar, "PCM signed 24-bit little-endian planar")
 
 PCM_CODEC (PCM_S32BE, AV_SAMPLE_FMT_S32, pcm_s32be, "PCM signed 32-bit big-endian")
 
 PCM_CODEC (PCM_S32LE, AV_SAMPLE_FMT_S32, pcm_s32le, "PCM signed 32-bit little-endian")
 
 PCM_CODEC (PCM_S32LE_PLANAR, AV_SAMPLE_FMT_S32P, pcm_s32le_planar, "PCM signed 32-bit little-endian planar")
 
 PCM_CODEC (PCM_U8, AV_SAMPLE_FMT_U8, pcm_u8, "PCM unsigned 8-bit")
 
 PCM_CODEC (PCM_U16BE, AV_SAMPLE_FMT_S16, pcm_u16be, "PCM unsigned 16-bit big-endian")
 
 PCM_CODEC (PCM_U16LE, AV_SAMPLE_FMT_S16, pcm_u16le, "PCM unsigned 16-bit little-endian")
 
 PCM_CODEC (PCM_U24BE, AV_SAMPLE_FMT_S32, pcm_u24be, "PCM unsigned 24-bit big-endian")
 
 PCM_CODEC (PCM_U24LE, AV_SAMPLE_FMT_S32, pcm_u24le, "PCM unsigned 24-bit little-endian")
 
 PCM_CODEC (PCM_U32BE, AV_SAMPLE_FMT_S32, pcm_u32be, "PCM unsigned 32-bit big-endian")
 
 PCM_CODEC (PCM_U32LE, AV_SAMPLE_FMT_S32, pcm_u32le, "PCM unsigned 32-bit little-endian")
 
 PCM_CODEC (PCM_S64BE, AV_SAMPLE_FMT_S64, pcm_s64be, "PCM signed 64-bit big-endian")
 
 PCM_CODEC (PCM_S64LE, AV_SAMPLE_FMT_S64, pcm_s64le, "PCM signed 64-bit little-endian")
 
 PCM_CODEC (PCM_VIDC, AV_SAMPLE_FMT_S16, pcm_vidc, "PCM Archimedes VIDC")
 
 PCM_DECODER (PCM_SGA, AV_SAMPLE_FMT_U8, pcm_sga, "PCM SGA")
 

Detailed Description

PCM codecs

Definition in file pcm.c.

Macro Definition Documentation

◆ INIT_ONCE

#define INIT_ONCE (   id,
  name 
)
Value:
case AV_CODEC_ID_PCM_ ## id: \
if (CONFIG_PCM_ ## id ## _ENCODER) { \
static AVOnce init_static_once = AV_ONCE_INIT; \
ff_thread_once(&init_static_once, pcm_ ## name ## _tableinit); \
} \
break

◆ ENCODE

#define ENCODE (   type,
  endian,
  src,
  dst,
  n,
  shift,
  offset 
)
Value:
samples_ ## type = (const type *) src; \
for (; n > 0; n--) { \
register type v = (*samples_ ## type++ >> shift) + offset; \
bytestream_put_ ## endian(&dst, v); \
}

Write PCM samples macro.

Parameters
typeDatatype of native machine format
endianbytestream_put_xxx() suffix
srcSource pointer (variable name)
dstDestination pointer (variable name)
nTotal number of samples (variable name)
shiftBitshift (bits)
offsetSample value offset

Definition at line 75 of file pcm.c.

◆ ENCODE_PLANAR

#define ENCODE_PLANAR (   type,
  endian,
  dst,
  n,
  shift,
  offset 
)
Value:
n /= avctx->channels; \
for (c = 0; c < avctx->channels; c++) { \
int i; \
samples_ ## type = (const type *) frame->extended_data[c]; \
for (i = n; i > 0; i--) { \
register type v = (*samples_ ## type++ >> shift) + offset; \
bytestream_put_ ## endian(&dst, v); \
} \
}

Definition at line 82 of file pcm.c.

◆ DECODE

#define DECODE (   size,
  endian,
  src,
  dst,
  n,
  shift,
  offset 
)
Value:
for (; n > 0; n--) { \
uint ## size ## _t v = bytestream_get_ ## endian(&src); \
AV_WN ## size ## A(dst, (uint ## size ## _t)(v - offset) << shift); \
dst += size / 8; \
}

Read PCM samples macro.

Parameters
sizeData size of native machine format
endianbytestream_get_xxx() endian suffix
srcSource pointer (variable name)
dstDestination pointer (variable name)
nTotal number of samples (variable name)
shiftBitshift (bits)
offsetSample value offset

Definition at line 307 of file pcm.c.

◆ DECODE_PLANAR

#define DECODE_PLANAR (   size,
  endian,
  src,
  dst,
  n,
  shift,
  offset 
)
Value:
n /= avctx->channels; \
for (c = 0; c < avctx->channels; c++) { \
int i; \
dst = frame->extended_data[c]; \
for (i = n; i > 0; i--) { \
uint ## size ## _t v = bytestream_get_ ## endian(&src); \
AV_WN ## size ## A(dst, (uint ## size ##_t)(v - offset) << shift); \
dst += size / 8; \
} \
}

Definition at line 314 of file pcm.c.

◆ PCM_ENCODER_0

#define PCM_ENCODER_0 (   id_,
  sample_fmt_,
  name_,
  long_name_ 
)

Definition at line 552 of file pcm.c.

◆ PCM_ENCODER_1

#define PCM_ENCODER_1 (   id_,
  sample_fmt_,
  name_,
  long_name_ 
)
Value:
const AVCodec ff_ ## name_ ## _encoder = { \
.name = #name_, \
.long_name = NULL_IF_CONFIG_SMALL(long_name_), \
.type = AVMEDIA_TYPE_AUDIO, \
.id = AV_CODEC_ID_ ## id_, \
.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_VARIABLE_FRAME_SIZE, \
.init = pcm_encode_init, \
.encode2 = pcm_encode_frame, \
.sample_fmts = (const enum AVSampleFormat[]){ sample_fmt_, \
AV_SAMPLE_FMT_NONE }, \
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE, \
}

Definition at line 553 of file pcm.c.

◆ PCM_ENCODER_2

#define PCM_ENCODER_2 (   cf,
  id,
  sample_fmt,
  name,
  long_name 
)    PCM_ENCODER_ ## cf(id, sample_fmt, name, long_name)

Definition at line 567 of file pcm.c.

◆ PCM_ENCODER_3

#define PCM_ENCODER_3 (   cf,
  id,
  sample_fmt,
  name,
  long_name 
)    PCM_ENCODER_2(cf, id, sample_fmt, name, long_name)

Definition at line 569 of file pcm.c.

◆ PCM_ENCODER

#define PCM_ENCODER (   id,
  sample_fmt,
  name,
  long_name 
)    PCM_ENCODER_3(CONFIG_ ## id ## _ENCODER, id, sample_fmt, name, long_name)

Definition at line 571 of file pcm.c.

◆ PCM_DECODER_0

#define PCM_DECODER_0 (   id,
  sample_fmt,
  name,
  long_name 
)

Definition at line 574 of file pcm.c.

◆ PCM_DECODER_1

#define PCM_DECODER_1 (   id_,
  sample_fmt_,
  name_,
  long_name_ 
)
Value:
const AVCodec ff_ ## name_ ## _decoder = { \
.name = #name_, \
.long_name = NULL_IF_CONFIG_SMALL(long_name_), \
.type = AVMEDIA_TYPE_AUDIO, \
.id = AV_CODEC_ID_ ## id_, \
.priv_data_size = sizeof(PCMDecode), \
.init = pcm_decode_init, \
.decode = pcm_decode_frame, \
.capabilities = AV_CODEC_CAP_DR1, \
.sample_fmts = (const enum AVSampleFormat[]){ sample_fmt_, \
AV_SAMPLE_FMT_NONE }, \
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE, \
}

Definition at line 575 of file pcm.c.

◆ PCM_DECODER_2

#define PCM_DECODER_2 (   cf,
  id,
  sample_fmt,
  name,
  long_name 
)    PCM_DECODER_ ## cf(id, sample_fmt, name, long_name)

Definition at line 590 of file pcm.c.

◆ PCM_DECODER_3

#define PCM_DECODER_3 (   cf,
  id,
  sample_fmt,
  name,
  long_name 
)    PCM_DECODER_2(cf, id, sample_fmt, name, long_name)

Definition at line 592 of file pcm.c.

◆ PCM_DECODER

#define PCM_DECODER (   id,
  sample_fmt,
  name,
  long_name 
)    PCM_DECODER_3(CONFIG_ ## id ## _DECODER, id, sample_fmt, name, long_name)

Definition at line 594 of file pcm.c.

◆ PCM_CODEC

#define PCM_CODEC (   id,
  sample_fmt_,
  name,
  long_name_ 
)
Value:
PCM_ENCODER(id, sample_fmt_, name, long_name_); \
PCM_DECODER(id, sample_fmt_, name, long_name_)

Definition at line 597 of file pcm.c.

Function Documentation

◆ pcm_encode_init()

static av_cold int pcm_encode_init ( AVCodecContext *  avctx)
static

Definition at line 38 of file pcm.c.

◆ pcm_encode_frame()

static int pcm_encode_frame ( AVCodecContext *  avctx,
AVPacket *  avpkt,
const AVFrame *  frame,
int *  got_packet_ptr 
)
static

Definition at line 93 of file pcm.c.

◆ pcm_decode_init()

static av_cold int pcm_decode_init ( AVCodecContext *  avctx)
static

Definition at line 249 of file pcm.c.

◆ pcm_decode_frame()

static int pcm_decode_frame ( AVCodecContext *  avctx,
void *  data,
int *  got_frame_ptr,
AVPacket *  avpkt 
)
static

Definition at line 326 of file pcm.c.

◆ PCM_CODEC() [1/29]

PCM_CODEC ( PCM_ALAW  ,
AV_SAMPLE_FMT_S16  ,
pcm_alaw  ,
"PCM A-law / G.711 A-law"   
)

◆ PCM_DECODER() [1/4]

PCM_DECODER ( PCM_F16LE  ,
AV_SAMPLE_FMT_FLT  ,
pcm_f16le  ,
"PCM 16.8 floating point little-endian"   
)

◆ PCM_DECODER() [2/4]

PCM_DECODER ( PCM_F24LE  ,
AV_SAMPLE_FMT_FLT  ,
pcm_f24le  ,
"PCM 24.0 floating point little-endian"   
)

◆ PCM_CODEC() [2/29]

PCM_CODEC ( PCM_F32BE  ,
AV_SAMPLE_FMT_FLT  ,
pcm_f32be  ,
"PCM 32-bit floating point big-endian"   
)

◆ PCM_CODEC() [3/29]

PCM_CODEC ( PCM_F32LE  ,
AV_SAMPLE_FMT_FLT  ,
pcm_f32le  ,
"PCM 32-bit floating point little-endian"   
)

◆ PCM_CODEC() [4/29]

PCM_CODEC ( PCM_F64BE  ,
AV_SAMPLE_FMT_DBL  ,
pcm_f64be  ,
"PCM 64-bit floating point big-endian"   
)

◆ PCM_CODEC() [5/29]

PCM_CODEC ( PCM_F64LE  ,
AV_SAMPLE_FMT_DBL  ,
pcm_f64le  ,
"PCM 64-bit floating point little-endian"   
)

◆ PCM_DECODER() [3/4]

PCM_DECODER ( PCM_LXF  ,
AV_SAMPLE_FMT_S32P  ,
pcm_lxf  ,
"PCM signed 20-bit little-endian planar"   
)

◆ PCM_CODEC() [6/29]

PCM_CODEC ( PCM_MULAW  ,
AV_SAMPLE_FMT_S16  ,
pcm_mulaw  ,
"PCM mu-law / G.711 mu-law"   
)

◆ PCM_CODEC() [7/29]

PCM_CODEC ( PCM_S8  ,
AV_SAMPLE_FMT_U8  ,
pcm_s8  ,
"PCM signed 8-bit"   
)

◆ PCM_CODEC() [8/29]

PCM_CODEC ( PCM_S8_PLANAR  ,
AV_SAMPLE_FMT_U8P  ,
pcm_s8_planar  ,
"PCM signed 8-bit planar"   
)

◆ PCM_CODEC() [9/29]

PCM_CODEC ( PCM_S16BE  ,
AV_SAMPLE_FMT_S16  ,
pcm_s16be  ,
"PCM signed 16-bit big-endian"   
)

◆ PCM_CODEC() [10/29]

PCM_CODEC ( PCM_S16BE_PLANAR  ,
AV_SAMPLE_FMT_S16P  ,
pcm_s16be_planar  ,
"PCM signed 16-bit big-endian planar"   
)

◆ PCM_CODEC() [11/29]

PCM_CODEC ( PCM_S16LE  ,
AV_SAMPLE_FMT_S16  ,
pcm_s16le  ,
"PCM signed 16-bit little-endian"   
)

◆ PCM_CODEC() [12/29]

PCM_CODEC ( PCM_S16LE_PLANAR  ,
AV_SAMPLE_FMT_S16P  ,
pcm_s16le_planar  ,
"PCM signed 16-bit little-endian planar"   
)

◆ PCM_CODEC() [13/29]

PCM_CODEC ( PCM_S24BE  ,
AV_SAMPLE_FMT_S32  ,
pcm_s24be  ,
"PCM signed 24-bit big-endian"   
)

◆ PCM_CODEC() [14/29]

PCM_CODEC ( PCM_S24DAUD  ,
AV_SAMPLE_FMT_S16  ,
pcm_s24daud  ,
"PCM D-Cinema audio signed 24-bit"   
)

◆ PCM_CODEC() [15/29]

PCM_CODEC ( PCM_S24LE  ,
AV_SAMPLE_FMT_S32  ,
pcm_s24le  ,
"PCM signed 24-bit little-endian"   
)

◆ PCM_CODEC() [16/29]

PCM_CODEC ( PCM_S24LE_PLANAR  ,
AV_SAMPLE_FMT_S32P  ,
pcm_s24le_planar  ,
"PCM signed 24-bit little-endian planar"   
)

◆ PCM_CODEC() [17/29]

PCM_CODEC ( PCM_S32BE  ,
AV_SAMPLE_FMT_S32  ,
pcm_s32be  ,
"PCM signed 32-bit big-endian"   
)

◆ PCM_CODEC() [18/29]

PCM_CODEC ( PCM_S32LE  ,
AV_SAMPLE_FMT_S32  ,
pcm_s32le  ,
"PCM signed 32-bit little-endian"   
)

◆ PCM_CODEC() [19/29]

PCM_CODEC ( PCM_S32LE_PLANAR  ,
AV_SAMPLE_FMT_S32P  ,
pcm_s32le_planar  ,
"PCM signed 32-bit little-endian planar"   
)

◆ PCM_CODEC() [20/29]

PCM_CODEC ( PCM_U8  ,
AV_SAMPLE_FMT_U8  ,
pcm_u8  ,
"PCM unsigned 8-bit"   
)

◆ PCM_CODEC() [21/29]

PCM_CODEC ( PCM_U16BE  ,
AV_SAMPLE_FMT_S16  ,
pcm_u16be  ,
"PCM unsigned 16-bit big-endian"   
)

◆ PCM_CODEC() [22/29]

PCM_CODEC ( PCM_U16LE  ,
AV_SAMPLE_FMT_S16  ,
pcm_u16le  ,
"PCM unsigned 16-bit little-endian"   
)

◆ PCM_CODEC() [23/29]

PCM_CODEC ( PCM_U24BE  ,
AV_SAMPLE_FMT_S32  ,
pcm_u24be  ,
"PCM unsigned 24-bit big-endian"   
)

◆ PCM_CODEC() [24/29]

PCM_CODEC ( PCM_U24LE  ,
AV_SAMPLE_FMT_S32  ,
pcm_u24le  ,
"PCM unsigned 24-bit little-endian"   
)

◆ PCM_CODEC() [25/29]

PCM_CODEC ( PCM_U32BE  ,
AV_SAMPLE_FMT_S32  ,
pcm_u32be  ,
"PCM unsigned 32-bit big-endian"   
)

◆ PCM_CODEC() [26/29]

PCM_CODEC ( PCM_U32LE  ,
AV_SAMPLE_FMT_S32  ,
pcm_u32le  ,
"PCM unsigned 32-bit little-endian"   
)

◆ PCM_CODEC() [27/29]

PCM_CODEC ( PCM_S64BE  ,
AV_SAMPLE_FMT_S64  ,
pcm_s64be  ,
"PCM signed 64-bit big-endian"   
)

◆ PCM_CODEC() [28/29]

PCM_CODEC ( PCM_S64LE  ,
AV_SAMPLE_FMT_S64  ,
pcm_s64le  ,
"PCM signed 64-bit little-endian"   
)

◆ PCM_CODEC() [29/29]

PCM_CODEC ( PCM_VIDC  ,
AV_SAMPLE_FMT_S16  ,
pcm_vidc  ,
"PCM Archimedes VIDC"   
)

◆ PCM_DECODER() [4/4]

PCM_DECODER ( PCM_SGA  ,
AV_SAMPLE_FMT_U8  ,
pcm_sga  ,
"PCM SGA"   
)
AVCodec
AVCodec.
Definition: codec.h:202
FF_CODEC_CAP_INIT_THREADSAFE
#define FF_CODEC_CAP_INIT_THREADSAFE
The codec does not modify any global variables in the init function, allowing to call the init functi...
Definition: internal.h:42
name
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 minimum maximum flags name is the option name
Definition: writing_filters.txt:88
sample_fmts
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:948
init
static int init
Definition: av_tx.c:47
A
#define A(x)
Definition: vp56_arith.h:28
type
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 type
Definition: writing_filters.txt:86
PCM_ENCODER
#define PCM_ENCODER(id, sample_fmt, name, long_name)
Definition: pcm.c:571
decode
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AV_ONCE_INIT
#define AV_ONCE_INIT
Definition: thread.h:173
src
#define src
Definition: vp8dsp.c:255
AV_CODEC_CAP_VARIABLE_FRAME_SIZE
#define AV_CODEC_CAP_VARIABLE_FRAME_SIZE
Audio encoder supports receiving a different number of samples in each call.
Definition: codec.h:134
pcm_decode_init
static av_cold int pcm_decode_init(AVCodecContext *avctx)
Definition: pcm.c:249
AVOnce
#define AVOnce
Definition: thread.h:172
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
for
for(j=16;j >0;--j)
Definition: h264pred_template.c:469
pcm_encode_frame
static int pcm_encode_frame(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
Definition: pcm.c:93
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
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:117
id
enum AVCodecID id
Definition: extract_extradata_bsf.c:325
size
int size
Definition: twinvq_data.h:10344
offset
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 offset
Definition: writing_filters.txt:86
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:209
pcm_decode_frame
static int pcm_decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
Definition: pcm.c:326
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
PCMDecode
Definition: pcm.c:242
shift
static int shift(int a, int b)
Definition: sonic.c:83
pcm_encode_init
static av_cold int pcm_encode_init(AVCodecContext *avctx)
Definition: pcm.c:38
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