2 * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 #include "mpegaudio.h"
24 AVBitStreamFilter *first_bitstream_filter= NULL;
26 void av_register_bitstream_filter(AVBitStreamFilter *bsf){
27 bsf->next = first_bitstream_filter;
28 first_bitstream_filter= bsf;
31 AVBitStreamFilterContext *av_bitstream_filter_init(const char *name){
32 AVBitStreamFilter *bsf= first_bitstream_filter;
35 if(!strcmp(name, bsf->name)){
36 AVBitStreamFilterContext *bsfc= av_mallocz(sizeof(AVBitStreamFilterContext));
38 bsfc->priv_data= av_mallocz(bsf->priv_data_size);
46 void av_bitstream_filter_close(AVBitStreamFilterContext *bsfc){
47 av_freep(&bsfc->priv_data);
48 av_parser_close(bsfc->parser);
52 int av_bitstream_filter_filter(AVBitStreamFilterContext *bsfc,
53 AVCodecContext *avctx, const char *args,
54 uint8_t **poutbuf, int *poutbuf_size,
55 const uint8_t *buf, int buf_size, int keyframe){
56 *poutbuf= (uint8_t *) buf;
57 *poutbuf_size= buf_size;
58 return bsfc->filter->filter(bsfc, avctx, args, poutbuf, poutbuf_size, buf, buf_size, keyframe);
61 static int dump_extradata(AVBitStreamFilterContext *bsfc, AVCodecContext *avctx, const char *args,
62 uint8_t **poutbuf, int *poutbuf_size,
63 const uint8_t *buf, int buf_size, int keyframe){
64 int cmd= args ? *args : 0;
65 /* cast to avoid warning about discarding qualifiers */
67 if( (keyframe && (avctx->flags2 & CODEC_FLAG2_LOCAL_HEADER) && cmd=='a')
68 ||(keyframe && (cmd=='k' || !cmd))
70 /*||(? && (s->flags & PARSER_FLAG_DUMP_EXTRADATA_AT_BEGIN)*/){
71 int size= buf_size + avctx->extradata_size;
73 *poutbuf= av_malloc(size + FF_INPUT_BUFFER_PADDING_SIZE);
75 memcpy(*poutbuf, avctx->extradata, avctx->extradata_size);
76 memcpy((*poutbuf) + avctx->extradata_size, buf, buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
83 static int remove_extradata(AVBitStreamFilterContext *bsfc, AVCodecContext *avctx, const char *args,
84 uint8_t **poutbuf, int *poutbuf_size,
85 const uint8_t *buf, int buf_size, int keyframe){
86 int cmd= args ? *args : 0;
87 AVCodecParserContext *s;
90 bsfc->parser= av_parser_init(avctx->codec_id);
94 if(s && s->parser->split){
95 if( (((avctx->flags & CODEC_FLAG_GLOBAL_HEADER) || (avctx->flags2 & CODEC_FLAG2_LOCAL_HEADER)) && cmd=='a')
96 ||(!keyframe && cmd=='k')
99 int i= s->parser->split(avctx, buf, buf_size);
104 *poutbuf= (uint8_t *) buf;
105 *poutbuf_size= buf_size;
110 static int noise(AVBitStreamFilterContext *bsfc, AVCodecContext *avctx, const char *args,
111 uint8_t **poutbuf, int *poutbuf_size,
112 const uint8_t *buf, int buf_size, int keyframe){
113 int amount= args ? atoi(args) : 10000;
114 unsigned int *state= bsfc->priv_data;
117 *poutbuf= av_malloc(buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
119 memcpy(*poutbuf, buf, buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
120 for(i=0; i<buf_size; i++){
121 (*state) += (*poutbuf)[i] + 1;
122 if(*state % amount == 0)
123 (*poutbuf)[i] = *state;
128 #define MP3_MASK 0xFFFE0CCF
130 static int mp3_header_compress(AVBitStreamFilterContext *bsfc, AVCodecContext *avctx, const char *args,
131 uint8_t **poutbuf, int *poutbuf_size,
132 const uint8_t *buf, int buf_size, int keyframe){
133 uint32_t header, extraheader;
134 int mode_extension, header_size;
136 if(avctx->strict_std_compliance > FF_COMPLIANCE_EXPERIMENTAL){
137 av_log(avctx, AV_LOG_ERROR, "not standards compliant\n");
141 header = AV_RB32(buf);
142 mode_extension= (header>>4)&3;
144 if(ff_mpa_check_header(header) < 0 || (header&0x60000) != 0x20000){
146 *poutbuf= (uint8_t *) buf;
147 *poutbuf_size= buf_size;
149 av_log(avctx, AV_LOG_INFO, "cannot compress %08X\n", header);
153 if(avctx->extradata_size == 0){
154 avctx->extradata_size=15;
155 avctx->extradata= av_malloc(avctx->extradata_size);
156 strcpy(avctx->extradata, "FFCMP3 0.0");
157 memcpy(avctx->extradata+11, buf, 4);
159 if(avctx->extradata_size != 15){
160 av_log(avctx, AV_LOG_ERROR, "Extradata invalid\n");
163 extraheader = AV_RB32(avctx->extradata+11);
164 if((extraheader&MP3_MASK) != (header&MP3_MASK))
165 goto output_unchanged;
167 header_size= (header&0x10000) ? 4 : 6;
169 *poutbuf_size= buf_size - header_size;
170 *poutbuf= av_malloc(buf_size - header_size + FF_INPUT_BUFFER_PADDING_SIZE);
171 memcpy(*poutbuf, buf + header_size, buf_size - header_size + FF_INPUT_BUFFER_PADDING_SIZE);
173 if(avctx->channels==2){
174 if((header & (3<<19)) != 3<<19){
175 (*poutbuf)[1] &= 0x3F;
176 (*poutbuf)[1] |= mode_extension<<6;
177 FFSWAP(int, (*poutbuf)[1], (*poutbuf)[2]);
179 (*poutbuf)[1] &= 0x8F;
180 (*poutbuf)[1] |= mode_extension<<4;
187 static int mp3_header_decompress(AVBitStreamFilterContext *bsfc, AVCodecContext *avctx, const char *args,
188 uint8_t **poutbuf, int *poutbuf_size,
189 const uint8_t *buf, int buf_size, int keyframe){
191 int sample_rate= avctx->sample_rate;
192 int sample_rate_index=0;
193 int lsf, mpeg25, bitrate_index, frame_size;
195 header = AV_RB32(buf);
196 if(ff_mpa_check_header(header) >= 0){
197 *poutbuf= (uint8_t *) buf;
198 *poutbuf_size= buf_size;
203 if(avctx->extradata_size != 15 || strcmp(avctx->extradata, "FFCMP3 0.0")){
204 av_log(avctx, AV_LOG_ERROR, "Extradata invalid %d\n", avctx->extradata_size);
208 header= AV_RB32(avctx->extradata+11) & MP3_MASK;
210 lsf = sample_rate < (24000+32000)/2;
211 mpeg25 = sample_rate < (12000+16000)/2;
212 sample_rate_index= (header>>10)&3;
213 sample_rate= mpa_freq_tab[sample_rate_index] >> (lsf + mpeg25); //in case sample rate is a little off
215 for(bitrate_index=2; bitrate_index<30; bitrate_index++){
216 frame_size = mpa_bitrate_tab[lsf][2][bitrate_index>>1];
217 frame_size = (frame_size * 144000) / (sample_rate << lsf) + (bitrate_index&1);
218 if(frame_size == buf_size + 4)
220 if(frame_size == buf_size + 6)
223 if(bitrate_index == 30){
224 av_log(avctx, AV_LOG_ERROR, "couldnt find bitrate_index\n");
228 header |= (bitrate_index&1)<<9;
229 header |= (bitrate_index>>1)<<12;
230 header |= (frame_size == buf_size + 4)<<16; //FIXME actually set a correct crc instead of 0
232 *poutbuf_size= frame_size;
233 *poutbuf= av_malloc(frame_size + FF_INPUT_BUFFER_PADDING_SIZE);
234 memcpy(*poutbuf + frame_size - buf_size, buf, buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
236 if(avctx->channels==2){
237 uint8_t *p= *poutbuf + frame_size - buf_size;
239 FFSWAP(int, p[1], p[2]);
240 header |= (p[1] & 0xC0)>>2;
243 header |= p[1] & 0x30;
248 (*poutbuf)[0]= header>>24;
249 (*poutbuf)[1]= header>>16;
250 (*poutbuf)[2]= header>> 8;
251 (*poutbuf)[3]= header ;
256 AVBitStreamFilter dump_extradata_bsf={
262 AVBitStreamFilter remove_extradata_bsf={
268 AVBitStreamFilter noise_bsf={
274 AVBitStreamFilter mp3_header_compress_bsf={
280 AVBitStreamFilter mp3_header_decompress_bsf={
283 mp3_header_decompress,