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ffmpeg.wasm-core
Commit 8424cf50 authored by Fabrice Bellard's avatar Fabrice Bellard
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new audio/video parser API 

Originally committed as revision 2492 to svn://svn.ffmpeg.org/ffmpeg/trunk
parent 962d6ae6
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Showing with 949 additions and 2 deletions
libavcodec/Makefile
View file @ 8424cf50
......@@ -19,7 +19,7 @@ OBJS= common.o utils.o mem.o allcodecs.o \
vp3.o asv1.o 4xm.o cabac.o ffv1.o ra144.o ra288.o vcr1.o cljr.o \
roqvideo.o dpcm.o interplayvideo.o xan.o rpza.o cinepak.o msrle.o \
msvideo1.o vqavideo.o idcinvideo.o adx.o rational.o faandct.o 8bps.o \
smc.o
smc.o parser.o
ifeq ($(AMR_NB),yes)
ifeq ($(AMR_NB_FIXED),yes)
......
libavcodec/allcodecs.c
View file @ 8424cf50
......@@ -193,5 +193,16 @@ PCM_CODEC(CODEC_ID_ADPCM_XA, adpcm_xa);
PCM_CODEC(CODEC_ID_ADPCM_ADX, adpcm_adx);
#undef PCM_CODEC
/* parsers */
av_register_codec_parser(&mpegvideo_parser);
av_register_codec_parser(&mpeg4video_parser);
av_register_codec_parser(&h263_parser);
av_register_codec_parser(&h264_parser);
av_register_codec_parser(&mpegaudio_parser);
#ifdef CONFIG_AC3
av_register_codec_parser(&ac3_parser);
#endif
}
libavcodec/avcodec.h
View file @ 8424cf50
......@@ -16,7 +16,7 @@ extern "C" {
#define FFMPEG_VERSION_INT 0x000408
#define FFMPEG_VERSION "0.4.8"
#define LIBAVCODEC_BUILD 4691
#define LIBAVCODEC_BUILD 4692
#define LIBAVCODEC_VERSION_INT FFMPEG_VERSION_INT
#define LIBAVCODEC_VERSION FFMPEG_VERSION
......@@ -1839,6 +1839,50 @@ typedef enum {
*/
int avcodec(void* handle, avc_cmd_t cmd, void* pin, void* pout);
/* frame parsing */
typedef struct AVCodecParserContext {
void *priv_data;
struct AVCodecParser *parser;
int64_t frame_offset; /* offset of the current frame */
int64_t cur_offset; /* current offset
(incremented by each av_parser_parse()) */
int64_t last_frame_offset; /* offset of the last frame */
/* video info */
int pict_type; /* XXX: put it back in AVCodecContext */
int repeat_pict; /* XXX: put it back in AVCodecContext */
int64_t pts; /* in us, if given by the codec (used by raw mpeg4) */
int64_t dts; /* in us, if given by the codec (used by raw mpeg4) */
} AVCodecParserContext;
typedef struct AVCodecParser {
int codec_ids[3]; /* several codec IDs are permitted */
int priv_data_size;
int (*parser_init)(AVCodecParserContext *s);
int (*parser_parse)(AVCodecParserContext *s,
AVCodecContext *avctx,
uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size);
void (*parser_close)(AVCodecParserContext *s);
struct AVCodecParser *next;
} AVCodecParser;
extern AVCodecParser *av_first_parser;
void av_register_codec_parser(AVCodecParser *parser);
AVCodecParserContext *av_parser_init(int codec_id);
int av_parser_parse(AVCodecParserContext *s,
AVCodecContext *avctx,
uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size);
void av_parser_close(AVCodecParserContext *s);
extern AVCodecParser mpegvideo_parser;
extern AVCodecParser mpeg4video_parser;
extern AVCodecParser h263_parser;
extern AVCodecParser h264_parser;
extern AVCodecParser mpegaudio_parser;
extern AVCodecParser ac3_parser;
/* memory */
void *av_malloc(unsigned int size);
void *av_mallocz(unsigned int size);
......
libavcodec/parser.c 0 → 100644
View file @ 8424cf50
/*
* Audio and Video frame extraction
* Copyright (c) 2003 Fabrice Bellard.
* Copyright (c) 2003 Michael Niedermayer.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "avcodec.h"
#include "mpegvideo.h"
#include "mpegaudio.h"
AVCodecParser *av_first_parser = NULL;
void av_register_codec_parser(AVCodecParser *parser)
{
parser->next = av_first_parser;
av_first_parser = parser;
}
AVCodecParserContext *av_parser_init(int codec_id)
{
AVCodecParserContext *s;
AVCodecParser *parser;
int ret;
for(parser = av_first_parser; parser != NULL; parser = parser->next) {
if (parser->codec_ids[0] == codec_id ||
parser->codec_ids[1] == codec_id ||
parser->codec_ids[2] == codec_id)
goto found;
}
return NULL;
found:
s = av_mallocz(sizeof(AVCodecParserContext));
if (!s)
return NULL;
s->parser = parser;
s->priv_data = av_mallocz(parser->priv_data_size);
if (!s->priv_data) {
av_free(s);
return NULL;
}
if (parser->parser_init) {
ret = parser->parser_init(s);
if (ret != 0) {
av_free(s->priv_data);
av_free(s);
return NULL;
}
}
return s;
}
int av_parser_parse(AVCodecParserContext *s,
AVCodecContext *avctx,
uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
int index;
/* WARNING: the returned index can be negative */
index = s->parser->parser_parse(s, avctx, poutbuf, poutbuf_size, buf, buf_size);
/* update the file pointer */
if (*poutbuf_size) {
s->frame_offset = s->last_frame_offset;
s->last_frame_offset = s->cur_offset + index;
}
if (index < 0)
index = 0;
s->cur_offset += index;
return index;
}
void av_parser_close(AVCodecParserContext *s)
{
if (s->parser->parser_close)
s->parser->parser_close(s);
av_free(s->priv_data);
av_free(s);
}
/*****************************************************/
//#define END_NOT_FOUND (-100)
#define PICTURE_START_CODE 0x00000100
#define SEQ_START_CODE 0x000001b3
#define EXT_START_CODE 0x000001b5
#define SLICE_MIN_START_CODE 0x00000101
#define SLICE_MAX_START_CODE 0x000001af
typedef struct ParseContext1{
uint8_t *buffer;
int index;
int last_index;
int buffer_size;
uint32_t state; ///< contains the last few bytes in MSB order
int frame_start_found;
int overread; ///< the number of bytes which where irreversibly read from the next frame
int overread_index; ///< the index into ParseContext1.buffer of the overreaded bytes
/* MPEG2 specific */
int frame_rate;
int progressive_sequence;
int width, height;
/* XXX: suppress that, needed by MPEG4 */
MpegEncContext *enc;
} ParseContext1;
/**
* combines the (truncated) bitstream to a complete frame
* @returns -1 if no complete frame could be created
*/
static int ff_combine_frame1(ParseContext1 *pc, int next, uint8_t **buf, int *buf_size)
{
#if 0
if(pc->overread){
printf("overread %d, state:%X next:%d index:%d o_index:%d\n", pc->overread, pc->state, next, pc->index, pc->overread_index);
printf("%X %X %X %X\n", (*buf)[0], (*buf)[1],(*buf)[2],(*buf)[3]);
}
#endif
/* copy overreaded bytes from last frame into buffer */
for(; pc->overread>0; pc->overread--){
pc->buffer[pc->index++]= pc->buffer[pc->overread_index++];
}
pc->last_index= pc->index;
/* copy into buffer end return */
if(next == END_NOT_FOUND){
pc->buffer= av_fast_realloc(pc->buffer, &pc->buffer_size, (*buf_size) + pc->index + FF_INPUT_BUFFER_PADDING_SIZE);
memcpy(&pc->buffer[pc->index], *buf, *buf_size);
pc->index += *buf_size;
return -1;
}
*buf_size=
pc->overread_index= pc->index + next;
/* append to buffer */
if(pc->index){
pc->buffer= av_fast_realloc(pc->buffer, &pc->buffer_size, next + pc->index + FF_INPUT_BUFFER_PADDING_SIZE);
memcpy(&pc->buffer[pc->index], *buf, next + FF_INPUT_BUFFER_PADDING_SIZE );
pc->index = 0;
*buf= pc->buffer;
}
/* store overread bytes */
for(;next < 0; next++){
pc->state = (pc->state<<8) | pc->buffer[pc->last_index + next];
pc->overread++;
}
#if 0
if(pc->overread){
printf("overread %d, state:%X next:%d index:%d o_index:%d\n", pc->overread, pc->state, next, pc->index, pc->overread_index);
printf("%X %X %X %X\n", (*buf)[0], (*buf)[1],(*buf)[2],(*buf)[3]);
}
#endif
return 0;
}
/**
* finds the end of the current frame in the bitstream.
* @return the position of the first byte of the next frame, or -1
*/
static int mpeg1_find_frame_end(ParseContext1 *pc, const uint8_t *buf, int buf_size)
{
int i;
uint32_t state;
state= pc->state;
i=0;
if(!pc->frame_start_found){
for(i=0; i<buf_size; i++){
state= (state<<8) | buf[i];
if(state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE){
i++;
pc->frame_start_found=1;
break;
}
}
}
if(pc->frame_start_found){
for(; i<buf_size; i++){
state= (state<<8) | buf[i];
if((state&0xFFFFFF00) == 0x100){
if(state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE){
pc->frame_start_found=0;
pc->state=-1;
return i-3;
}
}
}
}
pc->state= state;
return END_NOT_FOUND;
}
static int find_start_code(const uint8_t **pbuf_ptr, const uint8_t *buf_end)
{
const uint8_t *buf_ptr;
unsigned int state=0xFFFFFFFF, v;
int val;
buf_ptr = *pbuf_ptr;
while (buf_ptr < buf_end) {
v = *buf_ptr++;
if (state == 0x000001) {
state = ((state << 8) | v) & 0xffffff;
val = state;
goto found;
}
state = ((state << 8) | v) & 0xffffff;
}
val = -1;
found:
*pbuf_ptr = buf_ptr;
return val;
}
/* XXX: merge with libavcodec ? */
#define MPEG1_FRAME_RATE_BASE 1001
static const int frame_rate_tab[16] = {
0,
24000,
24024,
25025,
30000,
30030,
50050,
60000,
60060,
// Xing's 15fps: (9)
15015,
// libmpeg3's "Unofficial economy rates": (10-13)
5005,
10010,
12012,
15015,
// random, just to avoid segfault !never encode these
25025,
25025,
};
static void mpegvideo_extract_headers(AVCodecParserContext *s,
AVCodecContext *avctx,
const uint8_t *buf, int buf_size)
{
ParseContext1 *pc = s->priv_data;
const uint8_t *buf_end;
int32_t start_code;
int frame_rate_index, ext_type, bytes_left;
int frame_rate_ext_n, frame_rate_ext_d;
int top_field_first, repeat_first_field, progressive_frame;
int horiz_size_ext, vert_size_ext;
s->repeat_pict = 0;
buf_end = buf + buf_size;
while (buf < buf_end) {
start_code = find_start_code(&buf, buf_end);
bytes_left = buf_end - buf;
switch(start_code) {
case PICTURE_START_CODE:
if (bytes_left >= 2) {
s->pict_type = (buf[1] >> 3) & 7;
}
break;
case SEQ_START_CODE:
if (bytes_left >= 4) {
pc->width = avctx->width = (buf[0] << 4) | (buf[1] >> 4);
pc->height = avctx->height = ((buf[1] & 0x0f) << 8) | buf[2];
frame_rate_index = buf[3] & 0xf;
pc->frame_rate = avctx->frame_rate = frame_rate_tab[frame_rate_index];
avctx->frame_rate_base = MPEG1_FRAME_RATE_BASE;
}
break;
case EXT_START_CODE:
if (bytes_left >= 1) {
ext_type = (buf[0] >> 4);
switch(ext_type) {
case 0x1: /* sequence extension */
if (bytes_left >= 6) {
horiz_size_ext = ((buf[1] & 1) << 1) | (buf[2] >> 7);
vert_size_ext = (buf[2] >> 5) & 3;
frame_rate_ext_n = (buf[5] >> 5) & 3;
frame_rate_ext_d = (buf[5] & 0x1f);
pc->progressive_sequence = buf[1] & (1 << 3);
avctx->width = pc->width | (horiz_size_ext << 12);
avctx->height = pc->height | (vert_size_ext << 12);
avctx->frame_rate = pc->frame_rate * (frame_rate_ext_n + 1);
avctx->frame_rate_base = MPEG1_FRAME_RATE_BASE * (frame_rate_ext_d + 1);
avctx->sub_id = 2; /* forces MPEG2 */
}
break;
case 0x8: /* picture coding extension */
if (bytes_left >= 5) {
top_field_first = buf[3] & (1 << 7);
repeat_first_field = buf[3] & (1 << 1);
progressive_frame = buf[4] & (1 << 7);
/* check if we must repeat the frame */
if (repeat_first_field) {
if (pc->progressive_sequence) {
if (top_field_first)
s->repeat_pict = 4;
else
s->repeat_pict = 2;
} else if (progressive_frame) {
s->repeat_pict = 1;
}
}
}
break;
}
}
break;
case -1:
goto the_end;
default:
/* we stop parsing when we encounter a slice. It ensures
that this function takes a negligible amount of time */
if (start_code >= SLICE_MIN_START_CODE &&
start_code <= SLICE_MAX_START_CODE)
goto the_end;
break;
}
}
the_end: ;
}
static int mpegvideo_parse(AVCodecParserContext *s,
AVCodecContext *avctx,
uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
ParseContext1 *pc = s->priv_data;
int next;
next= mpeg1_find_frame_end(pc, buf, buf_size);
if (ff_combine_frame1(pc, next, (uint8_t **)&buf, &buf_size) < 0) {
*poutbuf = NULL;
*poutbuf_size = 0;
return buf_size;
}
/* we have a full frame : we just parse the first few MPEG headers
to have the full timing information. The time take by this
function should be negligible for uncorrupted streams */
mpegvideo_extract_headers(s, avctx, buf, buf_size);
#if 0
printf("pict_type=%d frame_rate=%0.3f repeat_pict=%d\n",
s->pict_type, (double)avctx->frame_rate / avctx->frame_rate_base, s->repeat_pict);
#endif
*poutbuf = (uint8_t *)buf;
*poutbuf_size = buf_size;
return next;
}
static void mpegvideo_parse_close(AVCodecParserContext *s)
{
ParseContext1 *pc = s->priv_data;
av_free(pc->buffer);
av_free(pc->enc);
}
/*************************/
/**
* finds the end of the current frame in the bitstream.
* @return the position of the first byte of the next frame, or -1
*/
static int mpeg4_find_frame_end(ParseContext1 *pc,
const uint8_t *buf, int buf_size)
{
int vop_found, i;
uint32_t state;
vop_found= pc->frame_start_found;
state= pc->state;
i=0;
if(!vop_found){
for(i=0; i<buf_size; i++){
state= (state<<8) | buf[i];
if(state == 0x1B6){
i++;
vop_found=1;
break;
}
}
}
if(vop_found){
for(; i<buf_size; i++){
state= (state<<8) | buf[i];
if((state&0xFFFFFF00) == 0x100){
pc->frame_start_found=0;
pc->state=-1;
return i-3;
}
}
}
pc->frame_start_found= vop_found;
pc->state= state;
return END_NOT_FOUND;
}
/* used by parser */
/* XXX: make it use less memory */
static int av_mpeg4_decode_header(AVCodecParserContext *s1,
AVCodecContext *avctx,
const uint8_t *buf, int buf_size)
{
ParseContext1 *pc = s1->priv_data;
MpegEncContext *s = pc->enc;
GetBitContext gb1, *gb = &gb1;
int ret;
s->avctx = avctx;
init_get_bits(gb, buf, 8 * buf_size);
ret = ff_mpeg4_decode_picture_header(s, gb);
if (s->width) {
avctx->width = s->width;
avctx->height = s->height;
}
return ret;
}
int mpeg4video_parse_init(AVCodecParserContext *s)
{
ParseContext1 *pc = s->priv_data;
pc->enc = av_mallocz(sizeof(MpegEncContext));
if (!pc->enc)
return -1;
return 0;
}
static int mpeg4video_parse(AVCodecParserContext *s,
AVCodecContext *avctx,
uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
ParseContext1 *pc = s->priv_data;
int next;
next= mpeg4_find_frame_end(pc, buf, buf_size);
if (ff_combine_frame1(pc, next, (uint8_t **)&buf, &buf_size) < 0) {
*poutbuf = NULL;
*poutbuf_size = 0;
return buf_size;
}
av_mpeg4_decode_header(s, avctx, buf, buf_size);
*poutbuf = (uint8_t *)buf;
*poutbuf_size = buf_size;
return next;
}
/*************************/
static int h263_find_frame_end(ParseContext1 *pc, const uint8_t *buf, int buf_size)
{
int vop_found, i;
uint32_t state;
vop_found= pc->frame_start_found;
state= pc->state;
i=0;
if(!vop_found){
for(i=0; i<buf_size; i++){
state= (state<<8) | buf[i];
if(state>>(32-22) == 0x20){
i++;
vop_found=1;
break;
}
}
}
if(vop_found){
for(; i<buf_size; i++){
state= (state<<8) | buf[i];
if(state>>(32-22) == 0x20){
pc->frame_start_found=0;
pc->state=-1;
return i-3;
}
}
}
pc->frame_start_found= vop_found;
pc->state= state;
return END_NOT_FOUND;
}
static int h263_parse(AVCodecParserContext *s,
AVCodecContext *avctx,
uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
ParseContext1 *pc = s->priv_data;
int next;
next= h263_find_frame_end(pc, buf, buf_size);
if (ff_combine_frame1(pc, next, (uint8_t **)&buf, &buf_size) < 0) {
*poutbuf = NULL;
*poutbuf_size = 0;
return buf_size;
}
*poutbuf = (uint8_t *)buf;
*poutbuf_size = buf_size;
return next;
}
/*************************/
/**
* finds the end of the current frame in the bitstream.
* @return the position of the first byte of the next frame, or -1
*/
static int h264_find_frame_end(ParseContext1 *pc, const uint8_t *buf, int buf_size)
{
int i;
uint32_t state;
//printf("first %02X%02X%02X%02X\n", buf[0], buf[1],buf[2],buf[3]);
// mb_addr= pc->mb_addr - 1;
state= pc->state;
//FIXME this will fail with slices
for(i=0; i<buf_size; i++){
state= (state<<8) | buf[i];
if((state&0xFFFFFF1F) == 0x101 || (state&0xFFFFFF1F) == 0x102 || (state&0xFFFFFF1F) == 0x105){
if(pc->frame_start_found){
pc->state=-1;
pc->frame_start_found= 0;
return i-3;
}
pc->frame_start_found= 1;
}
}
pc->state= state;
return END_NOT_FOUND;
}
static int h264_parse(AVCodecParserContext *s,
AVCodecContext *avctx,
uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
ParseContext1 *pc = s->priv_data;
int next;
next= h264_find_frame_end(pc, buf, buf_size);
if (ff_combine_frame1(pc, next, (uint8_t **)&buf, &buf_size) < 0) {
*poutbuf = NULL;
*poutbuf_size = 0;
return buf_size;
}
*poutbuf = (uint8_t *)buf;
*poutbuf_size = buf_size;
return next;
}
/*************************/
typedef struct MpegAudioParseContext {
uint8_t inbuf[MPA_MAX_CODED_FRAME_SIZE]; /* input buffer */
uint8_t *inbuf_ptr;
int frame_size;
int free_format_frame_size;
int free_format_next_header;
} MpegAudioParseContext;
#define MPA_HEADER_SIZE 4
/* header + layer + bitrate + freq + lsf/mpeg25 */
#define SAME_HEADER_MASK \
(0xffe00000 | (3 << 17) | (0xf << 12) | (3 << 10) | (3 << 19))
static int mpegaudio_parse_init(AVCodecParserContext *s1)
{
MpegAudioParseContext *s = s1->priv_data;
s->inbuf_ptr = s->inbuf;
return 0;
}
static int mpegaudio_parse(AVCodecParserContext *s1,
AVCodecContext *avctx,
uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
MpegAudioParseContext *s = s1->priv_data;
int len, ret;
uint32_t header;
const uint8_t *buf_ptr;
*poutbuf = NULL;
*poutbuf_size = 0;
buf_ptr = buf;
while (buf_size > 0) {
len = s->inbuf_ptr - s->inbuf;
if (s->frame_size == 0) {
/* special case for next header for first frame in free
format case (XXX: find a simpler method) */
if (s->free_format_next_header != 0) {
s->inbuf[0] = s->free_format_next_header >> 24;
s->inbuf[1] = s->free_format_next_header >> 16;
s->inbuf[2] = s->free_format_next_header >> 8;
s->inbuf[3] = s->free_format_next_header;
s->inbuf_ptr = s->inbuf + 4;
s->free_format_next_header = 0;
goto got_header;
}
/* no header seen : find one. We need at least MPA_HEADER_SIZE
bytes to parse it */
len = MPA_HEADER_SIZE - len;
if (len > buf_size)
len = buf_size;
if (len > 0) {
memcpy(s->inbuf_ptr, buf_ptr, len);
buf_ptr += len;
buf_size -= len;
s->inbuf_ptr += len;
}
if ((s->inbuf_ptr - s->inbuf) >= MPA_HEADER_SIZE) {
got_header:
header = (s->inbuf[0] << 24) | (s->inbuf[1] << 16) |
(s->inbuf[2] << 8) | s->inbuf[3];
ret = mpa_decode_header(avctx, header);
if (ret < 0) {
/* no sync found : move by one byte (inefficient, but simple!) */
memmove(s->inbuf, s->inbuf + 1, s->inbuf_ptr - s->inbuf - 1);
s->inbuf_ptr--;
dprintf("skip %x\n", header);
/* reset free format frame size to give a chance
to get a new bitrate */
s->free_format_frame_size = 0;
} else {
s->frame_size = ret;
#if 0
/* free format: prepare to compute frame size */
if (decode_header(s, header) == 1) {
s->frame_size = -1;
}
#endif
}
}
} else
#if 0
if (s->frame_size == -1) {
/* free format : find next sync to compute frame size */
len = MPA_MAX_CODED_FRAME_SIZE - len;
if (len > buf_size)
len = buf_size;
if (len == 0) {
/* frame too long: resync */
s->frame_size = 0;
memmove(s->inbuf, s->inbuf + 1, s->inbuf_ptr - s->inbuf - 1);
s->inbuf_ptr--;
} else {
uint8_t *p, *pend;
uint32_t header1;
int padding;
memcpy(s->inbuf_ptr, buf_ptr, len);
/* check for header */
p = s->inbuf_ptr - 3;
pend = s->inbuf_ptr + len - 4;
while (p <= pend) {
header = (p[0] << 24) | (p[1] << 16) |
(p[2] << 8) | p[3];
header1 = (s->inbuf[0] << 24) | (s->inbuf[1] << 16) |
(s->inbuf[2] << 8) | s->inbuf[3];
/* check with high probability that we have a
valid header */
if ((header & SAME_HEADER_MASK) ==
(header1 & SAME_HEADER_MASK)) {
/* header found: update pointers */
len = (p + 4) - s->inbuf_ptr;
buf_ptr += len;
buf_size -= len;
s->inbuf_ptr = p;
/* compute frame size */
s->free_format_next_header = header;
s->free_format_frame_size = s->inbuf_ptr - s->inbuf;
padding = (header1 >> 9) & 1;
if (s->layer == 1)
s->free_format_frame_size -= padding * 4;
else
s->free_format_frame_size -= padding;
dprintf("free frame size=%d padding=%d\n",
s->free_format_frame_size, padding);
decode_header(s, header1);
goto next_data;
}
p++;
}
/* not found: simply increase pointers */
buf_ptr += len;
s->inbuf_ptr += len;
buf_size -= len;
}
} else
#endif
if (len < s->frame_size) {
if (s->frame_size > MPA_MAX_CODED_FRAME_SIZE)
s->frame_size = MPA_MAX_CODED_FRAME_SIZE;
len = s->frame_size - len;
if (len > buf_size)
len = buf_size;
memcpy(s->inbuf_ptr, buf_ptr, len);
buf_ptr += len;
s->inbuf_ptr += len;
buf_size -= len;
}
// next_data:
if (s->frame_size > 0 &&
(s->inbuf_ptr - s->inbuf) >= s->frame_size) {
*poutbuf = s->inbuf;
*poutbuf_size = s->inbuf_ptr - s->inbuf;
s->inbuf_ptr = s->inbuf;
s->frame_size = 0;
break;
}
}
return buf_ptr - buf;
}
#ifdef CONFIG_AC3
extern int a52_syncinfo (const uint8_t * buf, int * flags,
int * sample_rate, int * bit_rate);
typedef struct AC3ParseContext {
uint8_t inbuf[4096]; /* input buffer */
uint8_t *inbuf_ptr;
int frame_size;
int flags;
} AC3ParseContext;
#define AC3_HEADER_SIZE 7
#define A52_LFE 16
static int ac3_parse_init(AVCodecParserContext *s1)
{
AC3ParseContext *s = s1->priv_data;
s->inbuf_ptr = s->inbuf;
return 0;
}
static int ac3_parse(AVCodecParserContext *s1,
AVCodecContext *avctx,
uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
AC3ParseContext *s = s1->priv_data;
const uint8_t *buf_ptr;
int len, sample_rate, bit_rate;
static const int ac3_channels[8] = {
2, 1, 2, 3, 3, 4, 4, 5
};
*poutbuf = NULL;
*poutbuf_size = 0;
buf_ptr = buf;
while (buf_size > 0) {
len = s->inbuf_ptr - s->inbuf;
if (s->frame_size == 0) {
/* no header seen : find one. We need at least 7 bytes to parse it */
len = AC3_HEADER_SIZE - len;
if (len > buf_size)
len = buf_size;
memcpy(s->inbuf_ptr, buf_ptr, len);
buf_ptr += len;
s->inbuf_ptr += len;
buf_size -= len;
if ((s->inbuf_ptr - s->inbuf) == AC3_HEADER_SIZE) {
len = a52_syncinfo(s->inbuf, &s->flags, &sample_rate, &bit_rate);
if (len == 0) {
/* no sync found : move by one byte (inefficient, but simple!) */
memmove(s->inbuf, s->inbuf + 1, AC3_HEADER_SIZE - 1);
s->inbuf_ptr--;
} else {
s->frame_size = len;
/* update codec info */
avctx->sample_rate = sample_rate;
avctx->channels = ac3_channels[s->flags & 7];
if (s->flags & A52_LFE)
avctx->channels++;
avctx->bit_rate = bit_rate;
avctx->frame_size = 6 * 256;
}
}
} else if (len < s->frame_size) {
len = s->frame_size - len;
if (len > buf_size)
len = buf_size;
memcpy(s->inbuf_ptr, buf_ptr, len);
buf_ptr += len;
s->inbuf_ptr += len;
buf_size -= len;
} else {
*poutbuf = s->inbuf;
*poutbuf_size = s->frame_size;
s->inbuf_ptr = s->inbuf;
s->frame_size = 0;
break;
}
}
return buf_ptr - buf;
}
#endif
AVCodecParser mpegvideo_parser = {
{ CODEC_ID_MPEG1VIDEO, CODEC_ID_MPEG2VIDEO },
sizeof(ParseContext1),
NULL,
mpegvideo_parse,
mpegvideo_parse_close,
};
AVCodecParser mpeg4video_parser = {
{ CODEC_ID_MPEG4 },
sizeof(ParseContext1),
mpeg4video_parse_init,
mpeg4video_parse,
mpegvideo_parse_close,
};
AVCodecParser h263_parser = {
{ CODEC_ID_H263 },
sizeof(ParseContext1),
NULL,
h263_parse,
mpegvideo_parse_close,
};
AVCodecParser h264_parser = {
{ CODEC_ID_H264 },
sizeof(ParseContext1),
NULL,
h264_parse,
mpegvideo_parse_close,
};
AVCodecParser mpegaudio_parser = {
{ CODEC_ID_MP2, CODEC_ID_MP3 },
sizeof(MpegAudioParseContext),
mpegaudio_parse_init,
mpegaudio_parse,
NULL,
};
#ifdef CONFIG_AC3
AVCodecParser ac3_parser = {
{ CODEC_ID_AC3 },
sizeof(AC3ParseContext),
ac3_parse_init,
ac3_parse,
NULL,
};
#endif
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