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Parse MP3 header to correct set the channel and samplerate

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This commit is contained in:
raven02 2014-04-10 18:51:54 +08:00
parent 6fe617d0ce
commit 97c68de661
1 changed files with 77 additions and 14 deletions
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91
Core/HLE/sceMp3.cpp
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@ -26,6 +26,8 @@
#include "Core/MemMap.h"
#include "Core/Reporting.h"
static const int ID3 = 0x49443300;
#ifdef USE_FFMPEG
#ifndef PRId64
#define PRId64 "%llu"
@ -340,9 +342,6 @@ u32 sceMp3ReserveMp3Handle(u32 mp3Addr) {
ctx->mp3DecodedBytes = 0;
ctx->mp3SumDecodedSamples = 0;
ctx->mp3LoopNum = -1;
ctx->mp3Channels = 2;
ctx->mp3Bitrate = 128;
ctx->mp3SamplingRate = 44100;
if (mp3Map.find(mp3Addr) != mp3Map.end()) {
delete mp3Map[mp3Addr];
@ -427,6 +426,72 @@ int __Mp3InitContext(Mp3Context *ctx) {
#endif
}
int __CalculateMp3Channels(int bitval) {
if (bitval == 0 || bitval == 1 || bitval == 2) { // Stereo / Joint Stereo / Dual Channel.
return 2;
} else if (bitval == 3) { // Mono.
return 1;
} else {
return -1;
}
}
int __CalculateMp3SampleRates(int bitval, int mp3version) {
if (mp3version == 3) { // MPEG Version 1
int valuemapping[] = { 44100, 48000, 32000, -1 };
return valuemapping[bitval];
} else if (mp3version == 2) { // MPEG Version 2
int valuemapping[] = { 22050, 24000, 16000, -1 };
return valuemapping[bitval];
} else if (mp3version == 0) { // MPEG Version 2.5
int valuemapping[] = { 11025, 12000, 8000, -1 };
return valuemapping[bitval];
} else {
return -1;
}
}
int __CalculateMp3Bitrates(int bitval, int mp3version, int mp3layer) {
if (mp3version == 3) { // MPEG Version 1
if (mp3layer == 3) { // Layer I
int valuemapping[] = { 0, 32, 64, 96, 128, 160, 192, 224, 256, 288, 320, 352, 384, 416, 448, -1 };
return valuemapping[bitval];
} else if (mp3layer == 2) { // Layer II
int valuemapping[] = { 0, 32, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 384, -1 };
return valuemapping[bitval];
} else if (mp3layer == 1) { // Layer III
int valuemapping[] = { 0, 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, -1 };
return valuemapping[bitval];
} else {
return -1;
}
} else if (mp3version == 2 || mp3version == 0) { // MPEG Version 2 or 2.5
if (mp3layer == 3) { // Layer I
int valuemapping[] = { 0, 32, 48, 56, 64, 80, 96, 112, 128, 144, 160, 176, 192, 224, 256, -1 };
return valuemapping[bitval];
} else if (mp3layer == 1 || mp3layer == 2) { // Layer II or III
int valuemapping[] = { 0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, -1 };
return valuemapping[bitval];
} else {
return -1;
}
} else {
return -1;
}
}
int __ParseMp3Header(Mp3Context *ctx) {
int header = bswap32(Memory::Read_U32(ctx->mp3Buf));
// ID3 tag , can be seen in Hanayaka Nari Wa ga Ichizoku.
if ((header & 0xFFFFFF00) == ID3) {
int size = bswap32(Memory::Read_U32(ctx->mp3Buf + ctx->mp3StreamStart + 6));
// Highest bit of each byte has to be ignored (format: 0x7F7F7F7F)
size = (size & 0x7F) | ((size & 0x7F00) >> 1) | ((size & 0x7F0000) >> 2) | ((size & 0x7F000000) >> 3);
header = bswap32(Memory::Read_U32(ctx->mp3Buf + ctx->mp3StreamStart + 10 + size));
}
return header;
}
int sceMp3Init(u32 mp3) {
DEBUG_LOG(ME, "sceMp3Init(%08x)", mp3);
@ -436,22 +501,20 @@ int sceMp3Init(u32 mp3) {
return -1;
}
// Read in the header and swap the endian
int header = bswap32(Memory::Read_U32(ctx->mp3Buf));
// Parse the Mp3 header
int header = __ParseMp3Header(ctx);
int layer = (header >> 17) & 0x3;
ctx->mp3Version = ((header >> 19) & 0x3);
ctx->mp3SamplingRate = __CalculateMp3SampleRates((header >> 10) & 0x3, ctx->mp3Version);
ctx->mp3Channels = __CalculateMp3Channels((header >> 6) & 0x3);
ctx->mp3Bitrate = __CalculateMp3Bitrates((header >> 12) & 0xF, ctx->mp3Version, layer);
INFO_LOG(ME, "sceMp3Init(): channels=%i, samplerate=%ikHz, bitrate=%ikbps", ctx->mp3Channels, ctx->mp3SamplingRate, ctx->mp3Bitrate);
#ifdef USE_FFMPEG
int ret = __Mp3InitContext(ctx);
if (ret != 0)
return ret;
// Let's just grab this info from FFMPEG, it seems more reliable than the code above.
ctx->mp3SamplingRate = ctx->decoder_context->sample_rate;
ctx->mp3Channels = ctx->decoder_context->channels;
ctx->mp3Bitrate = ctx->decoder_context->bit_rate / 1000;
INFO_LOG(ME, "sceMp3Init(): channels=%i, samplerate=%ikHz, bitrate=%ikbps", ctx->mp3Channels, ctx->mp3SamplingRate, ctx->mp3Bitrate);
return ret;
av_dump_format(ctx->avformat_context, 0, "mp3", 0);
#endif