[FFmpeg-cvslog] r19300 - trunk/libavcodec/mpegaudio_parser.c
michael
subversion
Tue Jun 30 05:12:51 CEST 2009
Author: michael
Date: Tue Jun 30 05:12:50 2009
New Revision: 19300
Log:
Rewrite mp3 parser. New code is much simpler and does not drop
stuff at random.
Modified:
trunk/libavcodec/mpegaudio_parser.c
Modified: trunk/libavcodec/mpegaudio_parser.c
==============================================================================
--- trunk/libavcodec/mpegaudio_parser.c Tue Jun 30 00:48:07 2009 (r19299)
+++ trunk/libavcodec/mpegaudio_parser.c Tue Jun 30 05:12:50 2009 (r19300)
@@ -26,11 +26,8 @@
typedef struct MpegAudioParseContext {
- uint8_t inbuf[MPA_MAX_CODED_FRAME_SIZE]; /* input buffer */
- uint8_t *inbuf_ptr;
+ ParseContext pc;
int frame_size;
- int free_format_frame_size;
- int free_format_next_header;
uint32_t header;
int header_count;
} MpegAudioParseContext;
@@ -81,174 +78,72 @@ int ff_mpa_decode_header(AVCodecContext
return s->frame_size;
}
-static av_cold 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,
const uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
MpegAudioParseContext *s = s1->priv_data;
- int len, ret, sr, channels, bit_rate, frame_size;
- uint32_t header;
- const uint8_t *buf_ptr;
+ ParseContext *pc = &s->pc;
+ uint32_t state= pc->state;
+ int i;
+ int next= END_NOT_FOUND;
- *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) {
- AV_WB32(s->inbuf, 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 = FFMIN(MPA_HEADER_SIZE - len, buf_size);
- if (len > 0) {
- memcpy(s->inbuf_ptr, buf_ptr, len);
- buf_ptr += len;
- buf_size -= len;
- s->inbuf_ptr += len;
+ for(i=0; i<buf_size; ){
+ if(s->frame_size){
+ int inc= FFMIN(buf_size - i, s->frame_size);
+ i += inc;
+ s->frame_size -= inc;
+
+ if(!s->frame_size){
+ next= i;
+ break;
}
- if ((s->inbuf_ptr - s->inbuf) >= MPA_HEADER_SIZE) {
- got_header:
- header = AV_RB32(s->inbuf);
+ }else{
+ while(i<buf_size){
+ int ret, sr, channels, bit_rate, frame_size;
- ret = ff_mpa_decode_header(avctx, header, &sr, &channels, &frame_size, &bit_rate);
- if (ret < 0) {
+ state= (state<<8) + buf[i++];
+
+ ret = ff_mpa_decode_header(avctx, state, &sr, &channels, &frame_size, &bit_rate);
+ if (ret < 4) {
s->header_count= -2;
- /* 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(avctx, "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 {
- if((header&SAME_HEADER_MASK) != (s->header&SAME_HEADER_MASK) && s->header)
+ if((state&SAME_HEADER_MASK) != (s->header&SAME_HEADER_MASK) && s->header)
s->header_count= -3;
- s->header= header;
+ s->header= state;
s->header_count++;
- s->frame_size = ret;
+ s->frame_size = ret-4;
-#if 0
- /* free format: prepare to compute frame size */
- if (ff_mpegaudio_decode_header((MPADecodeHeader *)s, header) == 1) {
- s->frame_size = -1;
- }
-#endif
if(s->header_count > 1){
avctx->sample_rate= sr;
avctx->channels = channels;
avctx->frame_size = frame_size;
avctx->bit_rate = bit_rate;
}
+ break;
}
}
- } 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 = AV_RB32(p);
- header1 = AV_RB32(s->inbuf);
- /* 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(avctx, "free frame size=%d padding=%d\n",
- s->free_format_frame_size, padding);
- ff_mpegaudio_decode_header((MPADecodeHeader *)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 = FFMIN(s->frame_size - len, buf_size);
- memcpy(s->inbuf_ptr, buf_ptr, len);
- buf_ptr += len;
- s->inbuf_ptr += len;
- buf_size -= len;
- }
-
- if(s->frame_size > 0 && buf_ptr - buf == s->inbuf_ptr - s->inbuf
- && buf_size + buf_ptr - buf >= s->frame_size){
- *poutbuf = buf;
- *poutbuf_size = s->frame_size;
- buf_ptr = buf + s->frame_size;
- s->inbuf_ptr = s->inbuf;
- s->frame_size = 0;
- break;
}
+ }
- // 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;
- }
+ pc->state= state;
+ if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
+ *poutbuf = NULL;
+ *poutbuf_size = 0;
+ return buf_size;
}
- return buf_ptr - buf;
+
+ *poutbuf = buf;
+ *poutbuf_size = buf_size;
+ return next;
}
AVCodecParser mpegaudio_parser = {
{ CODEC_ID_MP1, CODEC_ID_MP2, CODEC_ID_MP3 },
sizeof(MpegAudioParseContext),
- mpegaudio_parse_init,
+ NULL,
mpegaudio_parse,
NULL,
};
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