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adaptive spinup control

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git-svn-id: svn://svn.rockbox.org/rockbox/trunk@4599 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Jörg Hohensohn 2004-05-09 18:18:05 +00:00
parent 2fef5b7b4a
commit 12deda14d5
1 changed files with 32 additions and 7 deletions
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39
apps/plugins/video.c
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@ -43,8 +43,8 @@
#define FF_TICKS 3000; // experimentally found nice
// trigger levels, we need about 80 kB/sec
#define PRECHARGE (1024 * 64) // the initial filling before starting to play
#define SPINUP 3300 // from what level on to refill, in milliseconds
#define SPINUP_INIT 5000 // from what level on to refill, in milliseconds
#define SPINUP_SAFETY 700 // how much on top of the measured spinup time
#define CHUNK (1024*32) // read size
@ -148,6 +148,7 @@ static struct
bool bSeeking;
int nSeekAcc; // accelleration value for seek
int nSeekPos; // current file position for seek
bool bDiskSleep; // disk is suspended
} gPlay;
// buffer information
@ -166,6 +167,7 @@ static struct
bool bEOF; // flag for end of file
int low_water; // reload threshold
int high_water; // end of reload threshold
int spinup_safety; // safety margin when recalculating low_water
int nReadChunk; // how much data for normal buffer fill
int nSeekChunk; // how much data while seeking
} gBuf;
@ -177,6 +179,8 @@ static struct
int minVideoAvail;
int nAudioUnderruns;
int nVideoUnderruns;
long minSpinup;
long maxSpinup;
} gStats;
tFileHeader gFileHdr; // file header
@ -485,8 +489,8 @@ int SeekTo(int fd, int nPos)
gBuf.pBufFill = gBuf.pBufStart; // all empty
gBuf.pReadVideo = gBuf.pReadAudio = gBuf.pBufStart;
read_now = (PRECHARGE + gBuf.granularity - 1); // round up
read_now -= read_now % gBuf.granularity; // to granularity
read_now = gBuf.low_water - 1; // less than low water, so loading will continue
read_now -= read_now % gBuf.granularity; // round down to granularity
got_now = rb->read(fd, gBuf.pBufFill, read_now);
gBuf.bEOF = (read_now != got_now);
gBuf.pBufFill += got_now;
@ -574,6 +578,7 @@ int PlayTick(int fd)
{ // refill buffer
int read_now, got_now;
int buf_free;
long spinup; // measure the spinup time
// how much can we reload, don't fill completely, would appear empty
buf_free = gBuf.bufsize - MAX(avail_audio, avail_video) - gBuf.high_water;
@ -590,6 +595,8 @@ int PlayTick(int fd)
if (read_now == buf_free)
gPlay.bRefilling = false; // last piece requested
spinup = *rb->current_tick; // in case this is interesting below
got_now = rb->read(fd, gBuf.pBufFill, read_now);
if (got_now != read_now || read_now == 0)
{
@ -597,10 +604,25 @@ int PlayTick(int fd)
gPlay.bRefilling = false;
}
if (gPlay.bDiskSleep) // statistics about the spinup time
{
spinup = *rb->current_tick - spinup;
gPlay.bDiskSleep = false;
if (spinup > gStats.maxSpinup)
gStats.maxSpinup = spinup;
if (spinup < gStats.minSpinup)
gStats.minSpinup = spinup;
// recalculate the low water mark from real measurements
gBuf.low_water = (gStats.maxSpinup + gBuf.spinup_safety)
* gFileHdr.bps_peak / 8 / HZ;
}
if (!gPlay.bRefilling
&& rb->global_settings->disk_spindown < 20) // condition for test only
{
rb->ata_sleep(); // no point in leaving the disk run til timeout
gPlay.bDiskSleep = true;
}
gBuf.pBufFill += got_now;
@ -749,6 +771,7 @@ int PlayTick(int fd)
if ((gPlay.bAudioUnderrun || gPlay.bVideoUnderrun) && !gBuf.bEOF)
{
gBuf.spinup_safety += HZ/2; // add extra spinup time for the future
filepos = rb->lseek(fd, 0, SEEK_CUR);
if (gPlay.bHasVideo && gPlay.bVideoUnderrun)
@ -786,6 +809,7 @@ int main(char* filename)
// init statistics
rb->memset(&gStats, 0, sizeof(gStats));
gStats.minAudioAvail = gStats.minVideoAvail = INT_MAX;
gStats.minSpinup = INT_MAX;
// init playback state
rb->memset(&gPlay, 0, sizeof(gPlay));
@ -827,7 +851,8 @@ int main(char* filename)
gBuf.granularity *= 2;
gBuf.bufsize -= gBuf.bufsize % gBuf.granularity; // round down
gBuf.pBufEnd = gBuf.pBufStart + gBuf.bufsize;
gBuf.low_water = SPINUP * gFileHdr.bps_peak / 8000;
gBuf.low_water = SPINUP_INIT * gFileHdr.bps_peak / 8000;
gBuf.spinup_safety = SPINUP_SAFETY * HZ / 1000; // in time ticks
if (gFileHdr.audio_min_associated < 0)
gBuf.high_water = 0 - gFileHdr.audio_min_associated;
else
@ -897,9 +922,9 @@ int main(char* filename)
rb->lcd_puts(0, 2, gPrint);
rb->snprintf(gPrint, sizeof(gPrint), "%d MinVideo bytes", gStats.minVideoAvail);
rb->lcd_puts(0, 3, gPrint);
rb->snprintf(gPrint, sizeof(gPrint), "ReadChunk: %d", gBuf.nReadChunk);
rb->snprintf(gPrint, sizeof(gPrint), "MinSpinup %d.%02d", gStats.minSpinup/HZ, gStats.minSpinup%HZ);
rb->lcd_puts(0, 4, gPrint);
rb->snprintf(gPrint, sizeof(gPrint), "SeekChunk: %d", gBuf.nSeekChunk);
rb->snprintf(gPrint, sizeof(gPrint), "MaxSpinup %d.%02d", gStats.maxSpinup/HZ, gStats.maxSpinup%HZ);
rb->lcd_puts(0, 5, gPrint);
rb->snprintf(gPrint, sizeof(gPrint), "LowWater: %d", gBuf.low_water);
rb->lcd_puts(0, 6, gPrint);