actions/itgmania212121
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Much faster RageSoundReader_MP3::FindOffsetFix

Browse Source
This commit is contained in:
Glenn Maynard
2003-10-03 22:55:41 +00:00
parent ee9c02ea4e
commit 802d8c7aff
1 changed files with 22 additions and 23 deletions
Download Patch File Download Diff File Expand all files Collapse all files
stepmania/src/RageSoundReader_MP3.cpp
+22 -23
View File
@@ -439,8 +439,6 @@ int RageSoundReader_MP3::do_mad_frame_decode()
* so we can emulate that sync offset. */
int RageSoundReader_MP3::FindOffsetFix()
{
int i;
/* Do a fake rewind. */
if( fseek(this->rw, 0, SEEK_SET) == -1 )
{
@@ -461,8 +459,8 @@ int RageSoundReader_MP3::FindOffsetFix()
mad->first_frame = true;
/* Read a couple frames, to make sure we're synced. */
bool Silent = true;
for( i = 0; Silent || i < 5; ++i )
int FramesToRead = 5;
while( FramesToRead-- )
{
int ret = do_mad_frame_decode();
if( ret == 0 )
@@ -473,24 +471,28 @@ int RageSoundReader_MP3::FindOffsetFix()
if( ret == -1 )
return false; /* it set the error */
synth_output();
/* If this frame is silent, it's not an appropriate sample. Find
* a frame with actual sound in it. */
Silent = true;
for( unsigned j = 0; Silent && j < mad->outleft; ++j )
if( mad->outbuf[j] )
Silent=false;
}
if( !FramesToRead )
{
/* We've read enough frames. Now, make sure this frame isn't silent. */
bool Silent = true;
for( int j = 0; j < 2; ++j )
for( int k = 0; k < 36; ++k )
for( int l = 0; l < 32; ++l )
if( mad->Frame.sbsample[j][k][l] )
Silent=false;
/* If it's silent, it's not an appropriate sample. Find a frame
* with actual sound in it. */
if( Silent )
++FramesToRead;
}
if( Silent )
{
/* The sound didn't have any non-silent frames. */
MADLIB_rewind();
return true;
}
/* Clear the TOC cache. We might have cached bogus values. */
int i;
for( i = 0; i < 200; ++i)
mad->toc[i] = -1;
@@ -498,10 +500,9 @@ int RageSoundReader_MP3::FindOffsetFix()
* we decoded the last frame. */
mad_timer_t Apparent = mad->Timer;
/* Save the last frame's PCM data. */
unsigned size = mad->outleft;
char *cpy = new char[size];
memcpy( cpy, mad->outbuf, size );
/* Save the last frame's subband samples. */
mad_fixed_t cpy[2][36][32];
memcpy( cpy, mad->Frame.sbsample, sizeof(mad->Frame.sbsample) );
/* Do a real rewind. */
MADLIB_rewind();
@@ -520,8 +521,7 @@ int RageSoundReader_MP3::FindOffsetFix()
if( ret == -1 )
return false; /* it set the error */
synth_output();
if( mad->outleft == size && !memcmp( cpy, mad->outbuf, mad->outleft ) )
if( !memcmp( cpy, mad->Frame.sbsample, sizeof(mad->Frame.sbsample) ) )
{
/* Found it. Record that frame's real timestamp. */
Actual = mad->Timer;
@@ -540,7 +540,6 @@ int RageSoundReader_MP3::FindOffsetFix()
else
this->OffsetFix = 0;
delete [] cpy;
MADLIB_rewind();
return true;
}