diff options
Diffstat (limited to 'libmpdemux/demux_audio.c')
-rw-r--r-- | libmpdemux/demux_audio.c | 249 |
1 files changed, 249 insertions, 0 deletions
diff --git a/libmpdemux/demux_audio.c b/libmpdemux/demux_audio.c new file mode 100644 index 0000000000..a8c7bfb468 --- /dev/null +++ b/libmpdemux/demux_audio.c @@ -0,0 +1,249 @@ + +#include "config.h" + +#include <stdlib.h> +#include <stdio.h> +#include "stream.h" +#include "demuxer.h" +#include "stheader.h" +#include "genres.h" + +#include <string.h> +#ifdef MP_DEBUG +#include <assert.h> +#endif + +#define MP3 1 +#define WAV 2 + + +#define HDR_SIZE 4 + +typedef struct da_priv { + int frmt; +} da_priv_t; + +extern int mp_decode_mp3_header(unsigned char* hbuf); +extern void free_sh_audio(sh_audio_t* sh); + + +int demux_audio_open(demuxer_t* demuxer) { + stream_t *s; + sh_audio_t* sh_audio; + uint8_t hdr[HDR_SIZE]; + int st_pos = 0,frmt = 0, n = 0, pos = 0, step; + da_priv_t* priv; +#ifdef MP_DEBUG + assert(demuxer != NULL); + assert(demuxer->stream != NULL); +#endif + + s = demuxer->stream; + + while(n < 5 && ! s->eof) { + st_pos = stream_tell(s); + step = 1; + if(pos < HDR_SIZE) { + stream_read(s,&hdr[pos],HDR_SIZE-pos); + pos = HDR_SIZE; + } + + if( hdr[0] == 'R' && hdr[1] == 'I' && hdr[2] == 'F' && hdr[3] == 'F' ) { + stream_skip(s,4); + if(s->eof) + break; + stream_read(s,hdr,4); + if(s->eof) + break; + if(hdr[0] != 'W' || hdr[1] != 'A' || hdr[2] != 'V' || hdr[3] != 'E' ) + stream_skip(s,-8); + else + // We found wav header. Now we can have 'fmt ' or a mp3 header + // empty the buffer + step = 4; + } else if( hdr[0] == 'f' && hdr[1] == 'm' && hdr[2] == 't' && hdr[3] == ' ' ) { + frmt = WAV; + break; + } else if(mp_decode_mp3_header(hdr) > 0) { + frmt = MP3; + break; + } + // Add here some other audio format detection + if(step < HDR_SIZE) + memmove(hdr,&hdr[step],HDR_SIZE-step); + pos -= step; + } + + if(!frmt) + return 0; + + sh_audio = new_sh_audio(demuxer,0); + + switch(frmt) { + case MP3: + sh_audio->format = 0x55; + stream_seek(s,st_pos); + demuxer->movi_start = st_pos; + if(s->end_pos) { + char tag[4]; + stream_seek(s,s->end_pos-128); + stream_read(s,tag,3); + tag[3] = '\0'; + if(strcmp(tag,"TAG")) + demuxer->movi_end = s->end_pos; + else { + char buf[31]; + uint8_t g; + demuxer->movi_end = stream_tell(s)-3; + stream_read(s,buf,30); + buf[30] = '\0'; + demux_info_add(demuxer,"Title",buf); + stream_read(s,buf,30); + buf[30] = '\0'; + demux_info_add(demuxer,"Artist",buf); + stream_read(s,buf,30); + buf[30] = '\0'; + demux_info_add(demuxer,"Album",buf); + stream_read(s,buf,4); + buf[5] = '\0'; + demux_info_add(demuxer,"Year",buf); + stream_read(s,buf,30); + buf[30] = '\0'; + demux_info_add(demuxer,"Comment",buf); + if(buf[28] == 0 && buf[29] != 0) { + uint8_t trk = (uint8_t)buf[29]; + sprintf(buf,"%d",trk); + demux_info_add(demuxer,"Track",buf); + } + g = stream_read_char(s); + demux_info_add(demuxer,"Genre",genres[g]); + } + } + break; + case WAV: { + WAVEFORMATEX* w; + int l; + sh_audio->wf = w = (WAVEFORMATEX*)malloc(sizeof(WAVEFORMATEX)); + l = stream_read_dword_le(s); + if(l < 16) { + printf("Bad wav header length : too short !!!\n"); + free_sh_audio(sh_audio); + return 0; + } + w->wFormatTag = sh_audio->format = stream_read_word_le(s); + w->nChannels = sh_audio->channels = stream_read_word_le(s); + w->nSamplesPerSec = sh_audio->samplerate = stream_read_dword_le(s); + w->nAvgBytesPerSec = stream_read_dword_le(s); + w->nBlockAlign = stream_read_word_le(s); + w->wBitsPerSample = sh_audio->samplesize = stream_read_word_le(s); + w->cbSize = 0; + l -= 16; + if(l) + stream_skip(s,l); + demuxer->movi_start = stream_tell(s); + demuxer->movi_end = s->end_pos; + } break; + } + + priv = (da_priv_t*)malloc(sizeof(da_priv_t)); + priv->frmt = frmt; + demuxer->priv = priv; + demuxer->movi_start = st_pos; + demuxer->audio->id = 0; + demuxer->audio->sh = sh_audio; + sh_audio->ds = demuxer->audio; + + if(stream_tell(s) != demuxer->movi_start) + stream_seek(s,demuxer->movi_start); + + return 1; +} + + +int demux_audio_fill_buffer(demux_stream_t *ds) { + sh_audio_t* sh_audio; + demuxer_t* demux; + da_priv_t* priv; + stream_t* s; +#ifdef MP_DEBUG + assert(ds != NULL); + assert(ds->sh != NULL); + assert(ds->demuxer != NULL); +#endif + sh_audio = ds->sh; + demux = ds->demuxer; + priv = demux->priv; + s = demux->stream; + + if(s->eof || (demux->movi_end && stream_tell(s) >= demux->movi_end) ) + return 0; + + switch(priv->frmt) { + case MP3 : + while(! s->eof || (demux->movi_end && stream_tell(s) >= demux->movi_end) ) { + uint8_t hdr[4]; + int len; + stream_read(s,hdr,4); + len = mp_decode_mp3_header(hdr); + if(len < 0) { + stream_skip(s,-3); + } else { + demux_packet_t* dp; + if(s->eof || (demux->movi_end && stream_tell(s) >= demux->movi_end) ) + return 0; + dp = new_demux_packet(len); + memcpy(dp->buffer,hdr,4); + stream_read(s,dp->buffer + 4,len-4); + ds_add_packet(ds,dp); + return 1; + } + } + case WAV : { + int l = sh_audio->wf->nAvgBytesPerSec; + demux_packet_t* dp = new_demux_packet(l); + stream_read(s,dp->buffer,l); + ds_add_packet(ds,dp); + return 1; + } + default: + printf("Audio demuxer : unknow format %d\n",priv->frmt); + } + + + return 0; +} + +void demux_audio_seek(demuxer_t *demuxer,float rel_seek_secs,int flags){ + sh_audio_t* sh_audio; + stream_t* s; + int base,pos; + float len; + da_priv_t* priv; + + sh_audio = demuxer->audio->sh; + s = demuxer->stream; + priv = demuxer->priv; + + base = flags&1 ? demuxer->movi_start : stream_tell(s) ; + len = (demuxer->movi_end && flags&2) ? (demuxer->movi_end - demuxer->movi_start)*rel_seek_secs : rel_seek_secs; + + pos = base+(len*sh_audio->i_bps); + + if(demuxer->movi_end && pos >= demuxer->movi_end) { + sh_audio->timer = (stream_tell(s) - demuxer->movi_start)/sh_audio->i_bps; + return; + } else if(pos < demuxer->movi_start) + pos = demuxer->movi_start; + + + sh_audio->timer = flags&1 ? rel_seek_secs : (pos-demuxer->movi_start)/sh_audio->i_bps; + + switch(priv->frmt) { + case WAV: + pos += (pos % (sh_audio->channels * sh_audio->samplesize) ); + break; + } + + stream_seek(s,pos); + +} |