* Interface to libmp3lame for mp3 encoding
* Copyright (c) 2002 Lennert Buytenhek <buytenh@gnu.org>
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU 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 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 program is distributed in the hope that it will be useful,
+ * 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 General Public License for more details.
+ * 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 General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ * 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
+ */
+
+/**
+ * @file mp3lameaudio.c
+ * Interface to libmp3lame for mp3 encoding.
*/
#include "avcodec.h"
-#include <math.h>
#include "mpegaudio.h"
#include <lame/lame.h>
+#define BUFFER_SIZE (2*MPA_FRAME_SIZE)
typedef struct Mp3AudioContext {
lame_global_flags *gfp;
- int first_frame;
int stereo;
+ uint8_t buffer[BUFFER_SIZE];
+ int buffer_index;
} Mp3AudioContext;
-
static int MP3lame_encode_init(AVCodecContext *avctx)
{
Mp3AudioContext *s = avctx->priv_data;
if (avctx->channels > 2)
return -1;
- s->first_frame = 1;
s->stereo = avctx->channels > 1 ? 1 : 0;
if ((s->gfp = lame_init()) == NULL)
/* lame 3.91 doesn't work in mono */
lame_set_mode(s->gfp, JOINT_STEREO);
lame_set_brate(s->gfp, avctx->bit_rate/1000);
+ lame_set_bWriteVbrTag(s->gfp,0);
if (lame_init_params(s->gfp) < 0)
goto err_close;
- avctx->frame_size = MPA_FRAME_SIZE;
- avctx->key_frame = 1;
+ avctx->frame_size = lame_get_framesize(s->gfp);
+
+ avctx->coded_frame= avcodec_alloc_frame();
+ avctx->coded_frame->key_frame= 1;
return 0;
return -1;
}
+static const int sSampleRates[3] = {
+ 44100, 48000, 32000
+};
+
+static const int sBitRates[2][3][15] = {
+ { { 0, 32, 64, 96,128,160,192,224,256,288,320,352,384,416,448},
+ { 0, 32, 48, 56, 64, 80, 96,112,128,160,192,224,256,320,384},
+ { 0, 32, 40, 48, 56, 64, 80, 96,112,128,160,192,224,256,320}
+ },
+ { { 0, 32, 48, 56, 64, 80, 96,112,128,144,160,176,192,224,256},
+ { 0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96,112,128,144,160},
+ { 0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96,112,128,144,160}
+ },
+};
+
+static const int sSamplesPerFrame[2][3] =
+{
+ { 384, 1152, 1152 },
+ { 384, 1152, 576 }
+};
+
+static const int sBitsPerSlot[3] = {
+ 32,
+ 8,
+ 8
+};
+
+static int mp3len(void *data, int *samplesPerFrame, int *sampleRate)
+{
+ uint8_t *dataTmp = (uint8_t *)data;
+ uint32_t header = ( (uint32_t)dataTmp[0] << 24 ) | ( (uint32_t)dataTmp[1] << 16 ) | ( (uint32_t)dataTmp[2] << 8 ) | (uint32_t)dataTmp[3];
+ int layerID = 3 - ((header >> 17) & 0x03);
+ int bitRateID = ((header >> 12) & 0x0f);
+ int sampleRateID = ((header >> 10) & 0x03);
+ int bitsPerSlot = sBitsPerSlot[layerID];
+ int isPadded = ((header >> 9) & 0x01);
+ static int const mode_tab[4]= {2,3,1,0};
+ int mode= mode_tab[(header >> 19) & 0x03];
+ int mpeg_id= mode>0;
+ int temp0, temp1, bitRate;
+
+ if ( (( header >> 21 ) & 0x7ff) != 0x7ff || mode == 3 || layerID==3 || sampleRateID==3) {
+ return -1;
+ }
+
+ if(!samplesPerFrame) samplesPerFrame= &temp0;
+ if(!sampleRate ) sampleRate = &temp1;
+
+// *isMono = ((header >> 6) & 0x03) == 0x03;
+
+ *sampleRate = sSampleRates[sampleRateID]>>mode;
+ bitRate = sBitRates[mpeg_id][layerID][bitRateID] * 1000;
+ *samplesPerFrame = sSamplesPerFrame[mpeg_id][layerID];
+//av_log(NULL, AV_LOG_DEBUG, "sr:%d br:%d spf:%d l:%d m:%d\n", *sampleRate, bitRate, *samplesPerFrame, layerID, mode);
+
+ return *samplesPerFrame * bitRate / (bitsPerSlot * *sampleRate) + isPadded;
+}
+
int MP3lame_encode_frame(AVCodecContext *avctx,
unsigned char *frame, int buf_size, void *data)
{
Mp3AudioContext *s = avctx->priv_data;
- int num;
+ int len, i;
+ int lame_result;
/* lame 3.91 dies on '1-channel interleaved' data */
- if (s->stereo) {
- num = lame_encode_buffer_interleaved(s->gfp, data,
- MPA_FRAME_SIZE, frame, buf_size);
- } else {
- num = lame_encode_buffer(s->gfp, data, data, MPA_FRAME_SIZE,
- frame, buf_size);
- }
-
- /* lame 3.91 outputs the first frame as garbage */
- if (s->first_frame)
- s->first_frame = num = 0;
-
- return num;
+
+ if(data){
+ if (s->stereo) {
+ lame_result = lame_encode_buffer_interleaved(
+ s->gfp,
+ data,
+ avctx->frame_size,
+ s->buffer + s->buffer_index,
+ BUFFER_SIZE - s->buffer_index
+ );
+ } else {
+ lame_result = lame_encode_buffer(
+ s->gfp,
+ data,
+ data,
+ avctx->frame_size,
+ s->buffer + s->buffer_index,
+ BUFFER_SIZE - s->buffer_index
+ );
+ }
+ }else{
+ lame_result= lame_encode_flush(
+ s->gfp,
+ s->buffer + s->buffer_index,
+ BUFFER_SIZE - s->buffer_index
+ );
+ }
+
+ if(lame_result==-1) {
+ /* output buffer too small */
+ av_log(avctx, AV_LOG_ERROR, "lame: output buffer too small (buffer index: %d, free bytes: %d)\n", s->buffer_index, BUFFER_SIZE - s->buffer_index);
+ return 0;
+ }
+
+ s->buffer_index += lame_result;
+
+ if(s->buffer_index<4)
+ return 0;
+
+ len= mp3len(s->buffer, NULL, NULL);
+//av_log(avctx, AV_LOG_DEBUG, "in:%d packet-len:%d index:%d\n", avctx->frame_size, len, s->buffer_index);
+ if(len <= s->buffer_index){
+ memcpy(frame, s->buffer, len);
+ s->buffer_index -= len;
+
+ memmove(s->buffer, s->buffer+len, s->buffer_index);
+ //FIXME fix the audio codec API, so we dont need the memcpy()
+/*for(i=0; i<len; i++){
+ av_log(avctx, AV_LOG_DEBUG, "%2X ", frame[i]);
+}*/
+ return len;
+ }else
+ return 0;
}
int MP3lame_encode_close(AVCodecContext *avctx)
{
Mp3AudioContext *s = avctx->priv_data;
+
+ av_freep(&avctx->coded_frame);
lame_close(s->gfp);
return 0;
AVCodec mp3lame_encoder = {
"mp3",
CODEC_TYPE_AUDIO,
- CODEC_ID_MP3LAME,
+ CODEC_ID_MP3,
sizeof(Mp3AudioContext),
MP3lame_encode_init,
MP3lame_encode_frame,
- MP3lame_encode_close
+ MP3lame_encode_close,
+ .capabilities= CODEC_CAP_DELAY,
};