Add mpeg audio header parser

diff --git a/audioomx.cc b/audioomx.cc
index 5e5926bf26ffdeb9daf456f7d7e58370b799965a..cf4f564b1721ff7157ae4b9749264038d8abef5b 100644 (file)
--- a/audioomx.cc
+++ b/audioomx.cc
@@ -1566,8 +1566,46 @@ unsigned int AudioOMX::AdvanceMpAudioSync(const UCHAR *data,unsigned int size,un
        if (size<=2) return size; // silly;
        unsigned int test=0;
        *framesize=0;
+       //inspired by libav parsing code
        while (test+1<size) {
-               if (data[test]==0xFF && (data[test+1] &0xe0)==0xe0) return test; // probably FrameSync
+               if (data[test]==0xFF && (data[test+1] &0xe0)==0xe0) {
+                       const int sample_rates[4]={44100,48000,32000,0};
+                       const short bitrate_tab[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 } } };
+                       int lsf=0;
+                       int mpeg2=0;
+                       int layer=4-(data[test+2]&0x03)>>1;
+                       int bitrate_index=data[test+2]&0xf0>>4;
+                       int padding=(data[test+2]&2)>>1;
+                       if (0x10 &  data[test+1]) {
+                               lsf=((data[test+1]) &0x8)?0:1;
+                               mpeg2=0;
+                       } else {
+                               lsf=1;
+                               mpeg2=1;
+                       }
+                       int sample_rate=sample_rates[ (data[test+2]&0x0C)>>2]>>(lsf+mpeg2);
+                       int frame_size=bitrate_tab[lsf][layer - 1][bitrate_index];
+                       if (layer==1) {
+                               frame_size=(frame_size*12000)/sample_rate;
+                               frame_size=(frame_size+padding)*4;
+                       } else if (layer==2) {
+                               frame_size=(frame_size*144000)/sample_rate;
+                           frame_size=frame_size+padding;
+                       } else {
+                               frame_size=(frame_size*144000)/(sample_rate<<lsf);
+                               frame_size=frame_size+padding;
+                       }
+                       *framesize=frame_size;
+
+                       return test; // probably FrameSync
+               }
                test++;
        }
        return size;
@@ -1979,7 +2017,7 @@ UINT AudioOMX::DeliverMediaPacket(MediaPacket packet, const UCHAR* buffer,
                                        min(haveToCopy,decompress_buffer_size-decompress_buffer_filled));
                        incoming_paket_libav.size = decompress_buffer_filled
                                        +min(haveToCopy,decompress_buffer_size-decompress_buffer_filled);
-                       //Log::getInstance()->log("Audio", Log::DEBUG,"Use saved audio buffer %d %d %d",packet.type,decompress_buffer_filled,packet.synced);
+                       //Log::getInstance()->log("Audio", Log::DEBUG,"Use saved audio buffer %d %d %d",packet.type,decompress_buffer_filled,packet.synched);
                } else {
                        incoming_paket_libav.data =(uint8_t*) buffer+packet.pos_buffer+*samplepos;
                        incoming_paket_libav.size = haveToCopy;