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Cleanup code relative to bitstream.
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Remove lots of unnecessary malloc, free and assignment.
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@zhaoxiu-zeng
zhaoxiu-zeng committed Aug 13, 2014
1 parent 9802e2d commit c455e89
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Showing 6 changed files with 198 additions and 428 deletions.
4 changes: 2 additions & 2 deletions src/lib/bitstream.c
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Original file line number Diff line number Diff line change
Expand Up @@ -44,9 +44,9 @@ void shine_putbits(bitstream_t *bs, unsigned int val, unsigned int N)
#ifdef DEBUG
if (N > 32)
printf("Cannot write more than 32 bits at a time.\n");
if (N < 32 && (val >> N) != 0)
printf("Upper bits (higher than %d) are not all zeros.\n", N);
#endif
if (N < 32)
val &= ((1UL << N) - 1);

if (bs->cache_bits > N) {
bs->cache_bits -= N;
Expand Down
277 changes: 72 additions & 205 deletions src/lib/formatbits.c
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Original file line number Diff line number Diff line change
Expand Up @@ -15,7 +15,7 @@

/* In email <CAKheQp9H5-8eUeXtCahAhS-0pKOW1kZVC9xY0D0oLVfE_kPPMA@mail.gmail.com>,
* Mike Coleman <mc@fivebats.com> added the following regarding the code in this file:
*
*
* "As I recall, the intention of the ISO at the time was to be permissive
* with the code -- far more permissive than LGPL. In other words, do
* what you want with the code."
Expand All @@ -29,48 +29,36 @@

#include "types.h"
#include "formatbits.h"
#include "layer3.h"

/* forward declarations */
static int write_side_info(shine_global_config *config);
static void WriteMainDataBits( unsigned int val, unsigned int nbits, shine_global_config *config);

void shine_formatbits_initialise(shine_global_config *config)
/*
* WritePartMainData:
* ------------------
*/
static inline void WritePartMainData(BF_PartHolder *thePH, shine_global_config *config)
{
int ch, gr;
BF_BitstreamElement *ep, *end;

config->formatbits.BitCount = 0;
config->formatbits.BitsRemaining = config->mpeg.bits_per_frame;
config->formatbits.side_info.headerPH = NULL;
config->formatbits.side_info.frameSIPH = NULL;
/* assert(thePH); */

for ( ch = 0; ch < config->wave.channels; ch++ ) {
config->formatbits.side_info.channelSIPH[ch] = NULL;
for ( gr = 0; gr < config->mpeg.granules_per_frame; gr++ )
config->formatbits.side_info.spectrumSIPH[gr][ch] = NULL;
}
for (ep = thePH->element, end = ep + thePH->nrEntries; ep != end; ep++ )
WriteMainDataBits( ep->value, ep->length, config );
}

void shine_formatbits_close(shine_global_config *config)
static inline void WitePartSideInfo(BF_PartHolder *thePH, shine_global_config *config)
{
int ch, gr;
BF_BitstreamElement *ep, *end;

shine_BF_freePartHolder(config->formatbits.side_info.headerPH);

shine_BF_freePartHolder(config->formatbits.side_info.frameSIPH);
/* assert( thePH ); */

for ( ch = 0; ch < config->wave.channels; ch++ ) {
shine_BF_freePartHolder(config->formatbits.side_info.channelSIPH[ch]);

for ( gr = 0; gr < config->mpeg.granules_per_frame; gr++ )
shine_BF_freePartHolder(config->formatbits.side_info.spectrumSIPH[gr][ch]);
}
for (ep = thePH->element, end = ep + thePH->nrEntries; ep != end; ep++)
shine_putbits( &config->bs, ep->value, ep->length);
}

/* forward declarations */
static void store_side_info( shine_global_config *config );
static int write_side_info(shine_global_config *config);

static void main_data( shine_global_config *config);
static void WriteMainDataBits( unsigned int val, unsigned int nbits, shine_global_config *config);

static BF_PartHolder *BF_LoadHolderFromBitstreamPart( BF_PartHolder *theHolder, BF_BitstreamPart *thePart );

/*
* BF_BitStreamFrame:
* ------------------
Expand All @@ -88,59 +76,17 @@ static BF_PartHolder *BF_LoadHolderFromBitstreamPart( BF_PartHolder *theHolder,
* structures and the bitstream syntax.
*/
void shine_BF_BitstreamFrame(shine_global_config *config)
{
/* get ptr to bit writing function */
/* save SI and compute its length */
store_side_info( config );

/* write the main data, inserting SI to maintain framing */
main_data( config );

/*
* Caller must ensure that back SI and main data are
* an integral number of bytes, since the back pointer
* can only point to a byte boundary and this code
* does not add stuffing bits
*/
/* assert( (BitsRemaining % 8) == 0 );*/
}

/*
* WritePartMainData:
* ------------------
*/
static inline void WritePartMainData(BF_BitstreamPart *part, shine_global_config *config)
{
BF_BitstreamElement *ep, *end;

/* assert(part); */

for (ep = part->element, end = ep + part->nrEntries; ep != end; ep++ )
WriteMainDataBits( ep->value, ep->length, config );
}

static inline void WitePartSideInfo(BF_BitstreamPart *part, shine_global_config *config)
{
BF_BitstreamElement *ep, *end;

/* assert( part ); */

for (ep = part->element, end = ep + part->nrEntries; ep != end; ep++)
shine_putbits( &config->bs, ep->value, ep->length);
}

static void main_data(shine_global_config *config)
{
int gr, ch;

for (gr = 0; gr < config->mpeg.granules_per_frame; gr++)
for (ch = 0; ch < config->wave.channels; ch++)
{
WritePartMainData( config->l3stream.frameData.scaleFactors[gr][ch], config );
WritePartMainData( config->l3stream.frameData.codedData[gr][ch], config );
WritePartMainData( config->l3stream.frameData.userSpectrum[gr][ch], config );
WritePartMainData( &config->l3stream.scaleFactorsPH[gr][ch], config );
WritePartMainData( &config->l3stream.codedDataPH[gr][ch], config );
WritePartMainData( &config->l3stream.userSpectrumPH[gr][ch], config );
}
WritePartMainData( config->l3stream.frameData.userFrameData, config );
WritePartMainData( &config->l3stream.userFrameDataPH, config );
}

/*
Expand All @@ -156,24 +102,20 @@ static void WriteMainDataBits(unsigned int val,
unsigned int extra;

/* assert( nbits <= 32 ); */
if (config->formatbits.BitCount == config->mpeg.bits_per_frame)
{
config->formatbits.BitCount = write_side_info(config);
config->formatbits.BitsRemaining = config->mpeg.bits_per_frame - config->formatbits.BitCount;
}
if (nbits == 0) return;
if (nbits > config->formatbits.BitsRemaining)
{
extra = val >> (nbits - config->formatbits.BitsRemaining);
nbits -= config->formatbits.BitsRemaining;
shine_putbits( &config->bs, extra, config->formatbits.BitsRemaining);
config->formatbits.BitCount = write_side_info(config);
config->formatbits.BitsRemaining = config->mpeg.bits_per_frame - config->formatbits.BitCount;

if (nbits > config->l3stream.BitsRemaining) {
if (config->l3stream.BitsRemaining) {
nbits -= config->l3stream.BitsRemaining;
val &= (1UL << nbits) - 1;
extra = val >> nbits;
shine_putbits( &config->bs, extra, config->l3stream.BitsRemaining);
}
shine_putbits( &config->bs, val, nbits);

config->formatbits.BitCount += nbits;
config->formatbits.BitsRemaining -= nbits;
config->l3stream.BitsRemaining = config->mpeg.bits_per_frame - write_side_info(config);
}

shine_putbits( &config->bs, val, nbits);
config->l3stream.BitsRemaining -= nbits;
}

static int write_side_info(shine_global_config *config)
Expand All @@ -182,137 +124,62 @@ static int write_side_info(shine_global_config *config)

bits = shine_get_bits_count(&config->bs);

WitePartSideInfo( config->formatbits.side_info.headerPH->part, config );
WitePartSideInfo( config->formatbits.side_info.frameSIPH->part, config );
WitePartSideInfo( &config->l3stream.headerPH, config );
WitePartSideInfo( &config->l3stream.frameSIPH, config );

for ( ch = 0; ch < config->wave.channels; ch++ )
WitePartSideInfo( config->formatbits.side_info.channelSIPH[ch]->part, config );
if ( config->mpeg.version == MPEG_I )
for ( ch = 0; ch < config->wave.channels; ch++ )
WitePartSideInfo( &config->l3stream.channelSIPH[ch], config );

for ( gr = 0; gr < config->mpeg.granules_per_frame; gr++ )
for ( ch = 0; ch < config->wave.channels; ch++ )
WitePartSideInfo( config->formatbits.side_info.spectrumSIPH[gr][ch]->part, config );
return shine_get_bits_count(&config->bs) - bits;
}

static void store_side_info(shine_global_config *config)
{
int ch, gr;

if (config->formatbits.side_info.headerPH == NULL) { /* must allocate another */
config->formatbits.side_info.headerPH = shine_BF_newPartHolder( config->l3stream.frameData.header->nrEntries );
config->formatbits.side_info.frameSIPH = shine_BF_newPartHolder( config->l3stream.frameData.frameSI->nrEntries );

for ( ch = 0; ch < config->wave.channels; ch++ ) {
config->formatbits.side_info.channelSIPH[ch] = shine_BF_newPartHolder( config->l3stream.frameData.channelSI[ch]->nrEntries );
for ( gr = 0; gr < config->mpeg.granules_per_frame; gr++ )
config->formatbits.side_info.spectrumSIPH[gr][ch] = shine_BF_newPartHolder( config->l3stream.frameData.spectrumSI[gr][ch]->nrEntries );
}
}

/* copy data */
config->formatbits.side_info.headerPH = BF_LoadHolderFromBitstreamPart( config->formatbits.side_info.headerPH, config->l3stream.frameData.header );
config->formatbits.side_info.frameSIPH = BF_LoadHolderFromBitstreamPart( config->formatbits.side_info.frameSIPH, config->l3stream.frameData.frameSI );
WitePartSideInfo( &config->l3stream.spectrumSIPH[gr][ch], config );

for ( ch = 0; ch < config->wave.channels; ch++ ) {
config->formatbits.side_info.channelSIPH[ch] = BF_LoadHolderFromBitstreamPart(config->formatbits.side_info.channelSIPH[ch], config->l3stream.frameData.channelSI[ch]);
for ( gr = 0; gr < config->mpeg.granules_per_frame; gr++ )
config->formatbits.side_info.spectrumSIPH[gr][ch] = BF_LoadHolderFromBitstreamPart(config->formatbits.side_info.spectrumSIPH[gr][ch], config->l3stream.frameData.spectrumSI[gr][ch]);
}
return shine_get_bits_count(&config->bs) - bits;
}

/* Allocate a new holder of a given size */
BF_PartHolder *shine_BF_newPartHolder(unsigned int max_elements)
{
BF_PartHolder *newPH = calloc(1, sizeof(BF_PartHolder));
/* assert( newPH ); */
newPH->max_elements = max_elements;
newPH->part = calloc(1, sizeof(BF_BitstreamPart));
/* assert( newPH->part ); */
newPH->part->element = calloc((int)max_elements, sizeof(BF_BitstreamElement));
/* assert( newPH->part->element ); */
newPH->part->nrEntries = 0;
return newPH;
}

BF_PartHolder *shine_BF_NewHolderFromBitstreamPart( BF_BitstreamPart *thePart )
void shine_BF_initPartHolder(BF_PartHolder *thePH, unsigned int max_elements)
{
BF_PartHolder *newHolder = shine_BF_newPartHolder( thePart->nrEntries );
return BF_LoadHolderFromBitstreamPart( newHolder, thePart );
}

static BF_PartHolder *BF_LoadHolderFromBitstreamPart( BF_PartHolder *theHolder, BF_BitstreamPart *thePart )
{
BF_BitstreamElement *ep, *end;

theHolder->part->nrEntries = 0;

for (ep = thePart->element, end = ep + thePart->nrEntries; ep != end; ep++)
theHolder = shine_BF_addElement( theHolder, ep );

return theHolder;
}

/* Grow or shrink a part holder. Always creates a new one of the right length
and frees the old one after copying the data. */
BF_PartHolder *shine_BF_resizePartHolder( BF_PartHolder *oldPH, int max_elements )
{
int elems;
BF_PartHolder *newPH;

#ifdef DEBUG
printf("Resizing part holder from %d to %d\n", oldPH->max_elements, max_elements );
#endif
/* create new holder of the right length */
newPH = shine_BF_newPartHolder( max_elements );

/* copy values from old to new */
elems = (oldPH->max_elements > max_elements) ? max_elements : oldPH->max_elements;
newPH->part->nrEntries = elems;
memcpy(newPH->part->element, oldPH->part->element, elems * sizeof(newPH->part->element[0]));

/* free old holder */
shine_BF_freePartHolder( oldPH );

return newPH;
}

BF_PartHolder *shine_BF_freePartHolder( BF_PartHolder *thePH )
{
if (thePH == NULL) return NULL;

free( thePH->part->element );
free( thePH->part );
free( thePH );
return NULL;
thePH->nrEntries = 0;
thePH->max_elements = max_elements;
thePH->element = calloc((int)max_elements, sizeof(BF_BitstreamElement));
/* assert( thePH->element ); */
}

/* Add theElement to thePH, growing the holder if necessary. Returns ptr to the
holder, which may not be the one you called it with! */
BF_PartHolder *shine_BF_addElement( BF_PartHolder *thePH, BF_BitstreamElement *theElement )
void shine_BF_addElement( BF_PartHolder *thePH, BF_BitstreamElement *theElement )
{
BF_PartHolder *retPH = thePH;
int needed_entries = thePH->part->nrEntries + 1;
int extraPad = 8; /* add this many more if we need to resize */
int needed_entries = thePH->nrEntries + 1;
const int extraPad = 8; /* add this many more if we need to resize */

/* grow if necessary */
if ( needed_entries > thePH->max_elements )
retPH = shine_BF_resizePartHolder( thePH, needed_entries + extraPad );
if ( needed_entries > thePH->max_elements ) {
#ifdef DEBUG
printf("Resizing part holder from %d to %d\n", thePH->max_elements, thePH->max_elements + extraPad );
#endif

thePH->element = realloc(thePH->element, (thePH->max_elements + extraPad) * sizeof(BF_BitstreamElement));
/* assert( thePH->element ); */
thePH->max_elements += extraPad;
}

/* copy the data */
retPH->part->element[retPH->part->nrEntries++] = *theElement;
return retPH;
thePH->element[thePH->nrEntries++] = *theElement;
}

/* Add a bit value and length to the element list in thePH */
BF_PartHolder *shine_BF_addEntry( BF_PartHolder *thePH,
unsigned int value,
unsigned int length )
void shine_BF_addEntry( BF_PartHolder *thePH,
unsigned int value,
unsigned int length )
{
BF_BitstreamElement myElement;
myElement.value = value;
myElement.length = length;
if ( length )
return shine_BF_addElement( thePH, &myElement );
else
return thePH;
if ( length ) {
BF_BitstreamElement myElement;

myElement.value = value;
myElement.length = length;

shine_BF_addElement( thePH, &myElement );
}
}
16 changes: 3 additions & 13 deletions src/lib/formatbits.h
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Original file line number Diff line number Diff line change
Expand Up @@ -17,9 +17,6 @@

#include "types.h"

void shine_formatbits_initialise(shine_global_config *config);
void shine_formatbits_close(shine_global_config *config);

/*
The following is a shorthand bitstream syntax for
the type of bitstream this package will create.
Expand Down Expand Up @@ -63,17 +60,10 @@ MainData()
public functions in formatBitstream.c
*/

/* count the bits in a BitstreamPart */
int shine_BF_PartLength( BF_BitstreamPart *part );

/* encode a frame of audio and write it to your bitstream */
void shine_BF_BitstreamFrame( shine_global_config *config);

BF_PartHolder *shine_BF_newPartHolder( unsigned int max_elements );
BF_PartHolder *shine_BF_resizePartHolder( BF_PartHolder *oldPH, int max_elements );
BF_PartHolder *shine_BF_addElement( BF_PartHolder *thePH, BF_BitstreamElement *theElement );
BF_PartHolder *shine_BF_addEntry( BF_PartHolder *thePH, unsigned int value, unsigned int length );
BF_PartHolder *shine_BF_NewHolderFromBitstreamPart( BF_BitstreamPart *thePart );
BF_PartHolder *shine_BF_LoadHolderFromBitstreamPart( BF_PartHolder *theHolder, BF_BitstreamPart *thePart );
BF_PartHolder *shine_BF_freePartHolder( BF_PartHolder *thePH );
void shine_BF_initPartHolder( BF_PartHolder *thePH, unsigned int max_elements );
void shine_BF_addEntry( BF_PartHolder *thePH, unsigned int value, unsigned int length );

#endif
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