From c0c66dd81d232731c7bedfe56821de5fe233a081 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sun, 27 Aug 2006 11:42:40 +0000 Subject: [PATCH] fix low bitrate mp3 Originally committed as revision 6107 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/mpegaudiodec.c | 23 +++++++++++++++++------ 1 file changed, 17 insertions(+), 6 deletions(-) diff --git a/libavcodec/mpegaudiodec.c b/libavcodec/mpegaudiodec.c index 2d669a87eb..27a622c7d4 100644 --- a/libavcodec/mpegaudiodec.c +++ b/libavcodec/mpegaudiodec.c @@ -2517,15 +2517,26 @@ static int mp_decode_frame(MPADecodeContext *s, default: nb_frames = mp_decode_layer3(s); - if(s->in_gb.buffer) + s->last_buf_size=0; + if(s->in_gb.buffer){ + align_get_bits(&s->gb); + i= (s->gb.size_in_bits - get_bits_count(&s->gb))>>3; + if(i > 0 && i <= BACKSTEP_SIZE){ + memmove(s->last_buf, s->gb.buffer + (get_bits_count(&s->gb)>>3), i); + s->last_buf_size=i; + } 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; - if(s->last_buf_size <0 || s->last_buf_size > BACKSTEP_SIZE || nb_frames<0) - s->last_buf_size= FFMIN(BACKSTEP_SIZE, buf_size - HEADER_SIZE); - assert(s->last_buf_size <= buf_size - HEADER_SIZE); - memcpy(s->last_buf, s->gb.buffer + buf_size - HEADER_SIZE - s->last_buf_size, s->last_buf_size); + i= (s->gb.size_in_bits - get_bits_count(&s->gb))>>3; + + if(i<0 || s->last_buf_size + i > BACKSTEP_SIZE || nb_frames<0) + i= FFMIN(BACKSTEP_SIZE-s->last_buf_size, buf_size - HEADER_SIZE); + assert(i <= buf_size - HEADER_SIZE && i>= 0); + memcpy(s->last_buf + s->last_buf_size, s->gb.buffer + buf_size - HEADER_SIZE - i, i); + s->last_buf_size += i; break; }