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ffmpeg.wasm-core
Commit 06e7fb82 authored by Michael Niedermayer's avatar Michael Niedermayer
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remove duplicated parser, people who pass random gibblets of the bitstream... 

remove duplicated parser, people who pass random gibblets of the bitstream into the decoder will have to pass it through a AVParser like for all other codecs too
remove silly internal buffering architecture (removes 1 memcpy() of the bitstream)
mp3on4 and mp3adu untested

Originally committed as revision 6098 to svn://svn.ffmpeg.org/ffmpeg/trunk
parent 6e4703ca
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Showing with 123 additions and 223 deletions
libavcodec/mpegaudiodec.c
View file @ 06e7fb82
......@@ -85,13 +85,13 @@ static always_inline int MULH(int a, int b){
#define HEADER_SIZE 4
#define BACKSTEP_SIZE 512
#define EXTRABYTES 24
struct GranuleDef;
typedef struct MPADecodeContext {
uint8_t inbuf1[2][MPA_MAX_CODED_FRAME_SIZE + BACKSTEP_SIZE]; /* input buffer */
int inbuf_index;
uint8_t *inbuf_ptr, *inbuf;
DECLARE_ALIGNED_8(uint8_t, last_buf[BACKSTEP_SIZE + EXTRABYTES + MPA_MAX_CODED_FRAME_SIZE]); //FIXME we dont need that much
int last_buf_size;
int frame_size;
int free_format_frame_size; /* frame size in case of free format
(zero if currently unknown) */
......@@ -104,6 +104,7 @@ typedef struct MPADecodeContext {
int bit_rate;
int old_frame_size;
GetBitContext gb;
GetBitContext in_gb;
int nb_channels;
int mode;
int mode_ext;
......@@ -535,9 +536,6 @@ static int decode_init(AVCodecContext * avctx)
init = 1;
}
s->inbuf_index = 0;
s->inbuf = &s->inbuf1[s->inbuf_index][BACKSTEP_SIZE];
s->inbuf_ptr = s->inbuf;
#ifdef DEBUG
s->frame_count = 0;
#endif
......@@ -1585,29 +1583,6 @@ static int mp_decode_layer2(MPADecodeContext *s)
return 3 * 12;
}
/*
* Seek back in the stream for backstep bytes (at most 511 bytes)
*/
static void seek_to_maindata(MPADecodeContext *s, unsigned int backstep)
{
uint8_t *ptr;
/* compute current position in stream */
ptr = (uint8_t *)(s->gb.buffer + (get_bits_count(&s->gb)>>3));
/* copy old data before current one */
ptr -= backstep;
memcpy(ptr, s->inbuf1[s->inbuf_index ^ 1] +
BACKSTEP_SIZE + s->old_frame_size - backstep, backstep);
/* init get bits again */
init_get_bits(&s->gb, ptr, (s->frame_size + backstep)*8);
/* prepare next buffer */
s->inbuf_index ^= 1;
s->inbuf = &s->inbuf1[s->inbuf_index][BACKSTEP_SIZE];
s->old_frame_size = s->frame_size;
}
static inline void lsf_sf_expand(int *slen,
int sf, int n1, int n2, int n3)
{
......@@ -1676,12 +1651,13 @@ static inline int get_bitsz(GetBitContext *s, int n)
}
static int huffman_decode(MPADecodeContext *s, GranuleDef *g,
int16_t *exponents, int end_pos)
int16_t *exponents, int end_pos2)
{
int s_index;
int i;
int last_pos;
int last_pos, bits_left;
VLC *vlc;
int end_pos= FFMIN(end_pos2, s->gb.size_in_bits);
/* low frequencies (called big values) */
s_index = 0;
......@@ -1705,9 +1681,22 @@ static int huffman_decode(MPADecodeContext *s, GranuleDef *g,
/* read huffcode and compute each couple */
for(;j>0;j--) {
int exponent, x, y, v;
if (get_bits_count(&s->gb) >= end_pos)
int pos= get_bits_count(&s->gb);
if (pos >= end_pos){
// av_log(NULL, AV_LOG_ERROR, "pos: %d %d %d %d\n", pos, end_pos, end_pos2, s_index);
if(s->in_gb.buffer && pos >= s->gb.size_in_bits){
s->gb= s->in_gb;
s->in_gb.buffer=NULL;
assert((get_bits_count(&s->gb) & 7) == 0);
skip_bits_long(&s->gb, pos - end_pos);
end_pos= end_pos2 + get_bits_count(&s->gb) - pos;
pos= get_bits_count(&s->gb);
}
// av_log(NULL, AV_LOG_ERROR, "new pos: %d %d\n", pos, end_pos);
if(pos >= end_pos)
break;
}
y = get_vlc2(&s->gb, vlc->table, 7, 3);
if(!y){
......@@ -1768,13 +1757,24 @@ static int huffman_decode(MPADecodeContext *s, GranuleDef *g,
int pos, code;
pos = get_bits_count(&s->gb);
if (pos >= end_pos) {
if (pos > end_pos && last_pos){
// av_log(NULL, AV_LOG_ERROR, "pos2: %d %d %d %d\n", pos, end_pos, end_pos2, s_index);
if(s->in_gb.buffer && pos >= s->gb.size_in_bits){
s->gb= s->in_gb;
s->in_gb.buffer=NULL;
assert((get_bits_count(&s->gb) & 7) == 0);
skip_bits_long(&s->gb, pos - end_pos);
end_pos= end_pos2 + get_bits_count(&s->gb) - pos;
pos= get_bits_count(&s->gb);
}
// av_log(NULL, AV_LOG_ERROR, "new pos2: %d %d %d\n", pos, end_pos, s_index);
if (pos > end_pos && last_pos){ //FIXME last_pos is messed if we switch buffers
/* some encoders generate an incorrect size for this
part. We must go back into the data */
s_index -= 4;
init_get_bits(&s->gb, s->gb.buffer + 4*(last_pos>>5), s->gb.size_in_bits - (last_pos&(~31)));
skip_bits(&s->gb, last_pos&31);
skip_bits_long(&s->gb, last_pos - pos);
av_log(NULL, AV_LOG_ERROR, "overread, skip %d\n", last_pos&7);
}
if(pos >= end_pos)
break;
}
last_pos= pos;
......@@ -1799,6 +1799,16 @@ static int huffman_decode(MPADecodeContext *s, GranuleDef *g,
s_index+=4;
}
memset(&g->sb_hybrid[s_index], 0, sizeof(*g->sb_hybrid)*(576 - s_index));
/* skip extension bits */
bits_left = end_pos - get_bits_count(&s->gb);
//av_log(NULL, AV_LOG_ERROR, "left:%d buf:%p\n", bits_left, s->in_gb.buffer);
if (bits_left < 0) {
dprintf("bits_left=%d\n", bits_left);
return -1;
}
skip_bits_long(&s->gb, bits_left);
return 0;
}
......@@ -2184,7 +2194,7 @@ void sample_dump(int fnum, int32_t *tab, int n)
static int mp_decode_layer3(MPADecodeContext *s)
{
int nb_granules, main_data_begin, private_bits;
int gr, ch, blocksplit_flag, i, j, k, n, bits_pos, bits_left;
int gr, ch, blocksplit_flag, i, j, k, n, bits_pos;
GranuleDef granules[2][2], *g;
int16_t exponents[576];
......@@ -2308,9 +2318,18 @@ static int mp_decode_layer3(MPADecodeContext *s)
}
if (!s->adu_mode) {
const uint8_t *ptr = s->gb.buffer + (get_bits_count(&s->gb)>>3);
/* now we get bits from the main_data_begin offset */
dprintf("seekback: %d\n", main_data_begin);
seek_to_maindata(s, main_data_begin);
//av_log(NULL, AV_LOG_ERROR, "backstep:%d, lastbuf:%d\n", main_data_begin, s->last_buf_size);
if(main_data_begin > s->last_buf_size)
s->last_buf_size= main_data_begin;
memcpy(s->last_buf + s->last_buf_size, ptr, EXTRABYTES);
s->in_gb= s->gb;
init_get_bits(&s->gb, s->last_buf + s->last_buf_size - main_data_begin, main_data_begin*8);
/* prepare next buffer */
s->old_frame_size = s->frame_size;
}
for(gr=0;gr<nb_granules;gr++) {
......@@ -2452,19 +2471,6 @@ static int mp_decode_layer3(MPADecodeContext *s)
#if defined(DEBUG)
sample_dump(0, g->sb_hybrid, 576);
#endif
/* skip extension bits */
bits_left = g->part2_3_length - (get_bits_count(&s->gb) - bits_pos);
if (bits_left < 0) {
dprintf("bits_left=%d\n", bits_left);
return -1;
}
while (bits_left >= 16) {
skip_bits(&s->gb, 16);
bits_left -= 16;
}
if (bits_left > 0)
skip_bits(&s->gb, bits_left);
} /* ch */
if (s->nb_channels == 2)
......@@ -2491,13 +2497,12 @@ static int mp_decode_layer3(MPADecodeContext *s)
}
static int mp_decode_frame(MPADecodeContext *s,
OUT_INT *samples)
OUT_INT *samples, const uint8_t *buf, int buf_size)
{
int i, nb_frames, ch;
OUT_INT *samples_ptr;
init_get_bits(&s->gb, s->inbuf + HEADER_SIZE,
(s->inbuf_ptr - s->inbuf - HEADER_SIZE)*8);
init_get_bits(&s->gb, buf + HEADER_SIZE, (buf_size - HEADER_SIZE)*8);
/* skip error protection field */
if (s->error_protection)
......@@ -2514,6 +2519,14 @@ static int mp_decode_frame(MPADecodeContext *s,
case 3:
default:
nb_frames = mp_decode_layer3(s);
if(s->in_gb.buffer)
s->gb= s->in_gb;
align_get_bits(&s->gb);
assert((get_bits_count(&s->gb) & 7) == 0);
s->last_buf_size= (s->gb.size_in_bits - get_bits_count(&s->gb))>>3;
memcpy(s->last_buf, s->gb.buffer + (get_bits_count(&s->gb)>>3), s->last_buf_size);
break;
}
#if defined(DEBUG)
......@@ -2550,53 +2563,25 @@ static int decode_frame(AVCodecContext * avctx,
{
MPADecodeContext *s = avctx->priv_data;
uint32_t header;
uint8_t *buf_ptr;
int len, out_size;
int out_size;
OUT_INT *out_samples = data;
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 HEADER_SIZE
bytes to parse it */
len = 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) >= HEADER_SIZE) {
got_header:
header = (s->inbuf[0] << 24) | (s->inbuf[1] << 16) |
(s->inbuf[2] << 8) | s->inbuf[3];
if (ff_mpa_check_header(header) < 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 {
retry:
if(buf_size < HEADER_SIZE)
return -1;
header = (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3];
if(ff_mpa_check_header(header) < 0){
buf++;
// buf_size--;
av_log(avctx, AV_LOG_ERROR, "header missing skiping one byte\n");
goto retry;
}
if (decode_header(s, header) == 1) {
/* free format: prepare to compute frame size */
s->frame_size = -1;
return -1;
}
/* update codec info */
avctx->sample_rate = s->sample_rate;
......@@ -2617,92 +2602,19 @@ static int decode_frame(AVCodecContext * avctx,
avctx->frame_size = 1152;
break;
}
if(s->frame_size<=0 || s->frame_size < buf_size){
av_log(avctx, AV_LOG_ERROR, "incomplete frame\n");
return -1;
}
}
} else 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 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) {
if (avctx->parse_only) {
/* simply return the frame data */
*(uint8_t **)data = s->inbuf;
out_size = s->inbuf_ptr - s->inbuf;
} else {
out_size = mp_decode_frame(s, out_samples);
}
s->inbuf_ptr = s->inbuf;
s->frame_size = 0;
out_size = mp_decode_frame(s, out_samples, buf, buf_size);
if(out_size>=0)
*data_size = out_size;
else
av_log(avctx, AV_LOG_DEBUG, "Error while decoding mpeg audio frame\n"); //FIXME return -1 / but also return the number of bytes consumed
break;
}
}
return buf_ptr - buf;
s->frame_size = 0;
return buf_size;
}
......@@ -2727,12 +2639,8 @@ static int decode_frame_adu(AVCodecContext * avctx,
if (len > MPA_MAX_CODED_FRAME_SIZE)
len = MPA_MAX_CODED_FRAME_SIZE;
memcpy(s->inbuf, buf, len);
s->inbuf_ptr = s->inbuf + len;
// Get header and restore sync word
header = (s->inbuf[0] << 24) | (s->inbuf[1] << 16) |
(s->inbuf[2] << 8) | s->inbuf[3] | 0xffe00000;
header = (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3] | 0xffe00000;
if (ff_mpa_check_header(header) < 0) { // Bad header, discard frame
*data_size = 0;
......@@ -2749,11 +2657,9 @@ static int decode_frame_adu(AVCodecContext * avctx,
avctx->frame_size=s->frame_size = len;
if (avctx->parse_only) {
/* simply return the frame data */
*(uint8_t **)data = s->inbuf;
out_size = s->inbuf_ptr - s->inbuf;
out_size = buf_size;
} else {
out_size = mp_decode_frame(s, out_samples);
out_size = mp_decode_frame(s, out_samples, buf, buf_size);
}
*data_size = out_size;
......@@ -2816,8 +2722,6 @@ static int decode_init_mp3on4(AVCodecContext * avctx)
for (i = 1; i < s->frames; i++) {
s->mp3decctx[i] = av_mallocz(sizeof(MPADecodeContext));
s->mp3decctx[i]->compute_antialias = s->mp3decctx[0]->compute_antialias;
s->mp3decctx[i]->inbuf = &s->mp3decctx[i]->inbuf1[0][BACKSTEP_SIZE];
s->mp3decctx[i]->inbuf_ptr = s->mp3decctx[i]->inbuf;
s->mp3decctx[i]->adu_mode = 1;
}
......@@ -2877,13 +2781,9 @@ static int decode_frame_mp3on4(AVCodecContext * avctx,
fsize = MPA_MAX_CODED_FRAME_SIZE;
m = s->mp3decctx[fr];
assert (m != NULL);
/* copy original to new */
m->inbuf_ptr = m->inbuf + fsize;
memcpy(m->inbuf, start, fsize);
// Get header
header = (m->inbuf[0] << 24) | (m->inbuf[1] << 16) |
(m->inbuf[2] << 8) | m->inbuf[3] | 0xfff00000;
header = (start[0] << 24) | (start[1] << 16) | (start[2] << 8) | start[3] | 0xfff00000;
if (ff_mpa_check_header(header) < 0) { // Bad header, discard block
*data_size = 0;
......@@ -2891,7 +2791,7 @@ static int decode_frame_mp3on4(AVCodecContext * avctx,
}
decode_header(m, header);
mp_decode_frame(m, decoded_buf);
mp_decode_frame(m, decoded_buf, start, fsize);
n = MPA_FRAME_SIZE * m->nb_channels;
out_size += n * sizeof(OUT_INT);
......
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