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flac-lpc patch by (Justin Ruggles jruggle earthlink net)
tabs removed and regression.sh fixed (it was missing in the patch) by me Originally committed as revision 5572 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Justin Ruggles
Michael Niedermayer
parent
78f67b7ad3
commit
a403fc0324
@ -1983,6 +1983,58 @@ typedef struct AVCodecContext {
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* - decoding: unused
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*/
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int b_sensitivity;
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/**
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* - encoding: set by user.
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* - decoding: unused
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*/
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int compression_level;
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#define FF_COMPRESSION_DEFAULT -1
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/**
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* sets whether to use LPC mode - used by FLAC encoder
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* - encoding: set by user.
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* - decoding: unused.
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*/
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int use_lpc;
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/**
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* LPC coefficient precision - used by FLAC encoder
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* - encoding: set by user.
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* - decoding: unused.
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*/
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int lpc_coeff_precision;
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/**
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* - encoding: set by user.
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* - decoding: unused.
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*/
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int min_prediction_order;
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/**
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* - encoding: set by user.
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* - decoding: unused.
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*/
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int max_prediction_order;
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/**
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* search method for selecting prediction order
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* - encoding: set by user.
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* - decoding: unused.
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*/
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int prediction_order_method;
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/**
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* - encoding: set by user.
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* - decoding: unused.
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*/
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int min_partition_order;
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/**
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* - encoding: set by user.
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* - decoding: unused.
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*/
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int max_partition_order;
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} AVCodecContext;
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/**
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@ -37,11 +37,38 @@
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#define FLAC_CHMODE_RIGHT_SIDE 9
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#define FLAC_CHMODE_MID_SIDE 10
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#define ORDER_METHOD_EST 0
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#define ORDER_METHOD_2LEVEL 1
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#define ORDER_METHOD_4LEVEL 2
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#define ORDER_METHOD_8LEVEL 3
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#define ORDER_METHOD_SEARCH 4
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#define FLAC_STREAMINFO_SIZE 34
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#define MIN_LPC_ORDER 1
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#define MAX_LPC_ORDER 32
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#define MAX_FIXED_ORDER 4
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#define MAX_PARTITION_ORDER 8
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#define MAX_PARTITIONS (1 << MAX_PARTITION_ORDER)
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#define MAX_LPC_PRECISION 15
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#define MAX_LPC_SHIFT 15
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#define MAX_RICE_PARAM 14
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typedef struct CompressionOptions {
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int compression_level;
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int block_time_ms;
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int use_lpc;
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int lpc_coeff_precision;
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int min_prediction_order;
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int max_prediction_order;
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int prediction_order_method;
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int min_partition_order;
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int max_partition_order;
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} CompressionOptions;
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typedef struct RiceContext {
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int porder;
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int params[256];
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int params[MAX_PARTITIONS];
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} RiceContext;
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typedef struct FlacSubframe {
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@ -49,6 +76,8 @@ typedef struct FlacSubframe {
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int type_code;
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int obits;
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int order;
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int32_t coefs[MAX_LPC_ORDER];
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int shift;
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RiceContext rc;
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int32_t samples[FLAC_MAX_BLOCKSIZE];
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int32_t residual[FLAC_MAX_BLOCKSIZE];
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@ -72,6 +101,7 @@ typedef struct FlacEncodeContext {
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int max_framesize;
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uint32_t frame_count;
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FlacFrame frame;
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CompressionOptions options;
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AVCodecContext *avctx;
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} FlacEncodeContext;
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@ -112,13 +142,11 @@ static void write_streaminfo(FlacEncodeContext *s, uint8_t *header)
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/* MD5 signature = 0 */
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}
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#define BLOCK_TIME_MS 27
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/**
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* Sets blocksize based on samplerate
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* Chooses the closest predefined blocksize >= BLOCK_TIME_MS milliseconds
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*/
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static int select_blocksize(int samplerate)
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static int select_blocksize(int samplerate, int block_time_ms)
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{
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int i;
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int target;
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@ -126,7 +154,7 @@ static int select_blocksize(int samplerate)
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assert(samplerate > 0);
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blocksize = flac_blocksizes[1];
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target = (samplerate * BLOCK_TIME_MS) / 1000;
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target = (samplerate * block_time_ms) / 1000;
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for(i=0; i<16; i++) {
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if(target >= flac_blocksizes[i] && flac_blocksizes[i] > blocksize) {
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blocksize = flac_blocksizes[i];
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@ -183,8 +211,198 @@ static int flac_encode_init(AVCodecContext *avctx)
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s->samplerate = freq;
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}
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s->blocksize = select_blocksize(s->samplerate);
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avctx->frame_size = s->blocksize;
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/* set compression option defaults based on avctx->compression_level */
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if(avctx->compression_level < 0) {
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s->options.compression_level = 5;
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} else {
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s->options.compression_level = avctx->compression_level;
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}
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av_log(avctx, AV_LOG_DEBUG, " compression: %d\n", s->options.compression_level);
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if(s->options.compression_level == 0) {
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s->options.block_time_ms = 27;
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s->options.use_lpc = 0;
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s->options.min_prediction_order = 2;
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s->options.max_prediction_order = 3;
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s->options.prediction_order_method = ORDER_METHOD_EST;
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s->options.min_partition_order = 2;
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s->options.max_partition_order = 2;
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} else if(s->options.compression_level == 1) {
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s->options.block_time_ms = 27;
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s->options.use_lpc = 0;
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s->options.min_prediction_order = 0;
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s->options.max_prediction_order = 4;
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s->options.prediction_order_method = ORDER_METHOD_EST;
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s->options.min_partition_order = 2;
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s->options.max_partition_order = 2;
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} else if(s->options.compression_level == 2) {
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s->options.block_time_ms = 27;
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s->options.use_lpc = 0;
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s->options.min_prediction_order = 0;
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s->options.max_prediction_order = 4;
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s->options.prediction_order_method = ORDER_METHOD_EST;
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s->options.min_partition_order = 0;
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s->options.max_partition_order = 3;
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} else if(s->options.compression_level == 3) {
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s->options.block_time_ms = 105;
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s->options.use_lpc = 1;
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s->options.min_prediction_order = 1;
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s->options.max_prediction_order = 6;
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s->options.prediction_order_method = ORDER_METHOD_EST;
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s->options.min_partition_order = 0;
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s->options.max_partition_order = 3;
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} else if(s->options.compression_level == 4) {
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s->options.block_time_ms = 105;
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s->options.use_lpc = 1;
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s->options.min_prediction_order = 1;
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s->options.max_prediction_order = 8;
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s->options.prediction_order_method = ORDER_METHOD_EST;
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s->options.min_partition_order = 0;
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s->options.max_partition_order = 3;
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} else if(s->options.compression_level == 5) {
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s->options.block_time_ms = 105;
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s->options.use_lpc = 1;
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s->options.min_prediction_order = 1;
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s->options.max_prediction_order = 8;
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s->options.prediction_order_method = ORDER_METHOD_EST;
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s->options.min_partition_order = 0;
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s->options.max_partition_order = 8;
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} else {
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av_log(avctx, AV_LOG_ERROR, "invalid compression level: %d\n",
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s->options.compression_level);
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return -1;
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}
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/* set compression option overrides from AVCodecContext */
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if(avctx->use_lpc >= 0) {
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s->options.use_lpc = !!avctx->use_lpc;
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}
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av_log(avctx, AV_LOG_DEBUG, " use lpc: %s\n",
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s->options.use_lpc? "yes" : "no");
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if(avctx->min_prediction_order >= 0) {
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if(s->options.use_lpc) {
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if(avctx->min_prediction_order < MIN_LPC_ORDER ||
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avctx->min_prediction_order > MAX_LPC_ORDER) {
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av_log(avctx, AV_LOG_ERROR, "invalid min prediction order: %d\n",
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avctx->min_prediction_order);
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return -1;
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}
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} else {
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if(avctx->min_prediction_order > MAX_FIXED_ORDER) {
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av_log(avctx, AV_LOG_ERROR, "invalid min prediction order: %d\n",
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avctx->min_prediction_order);
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return -1;
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}
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}
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s->options.min_prediction_order = avctx->min_prediction_order;
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}
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if(avctx->max_prediction_order >= 0) {
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if(s->options.use_lpc) {
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if(avctx->max_prediction_order < MIN_LPC_ORDER ||
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avctx->max_prediction_order > MAX_LPC_ORDER) {
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av_log(avctx, AV_LOG_ERROR, "invalid max prediction order: %d\n",
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avctx->max_prediction_order);
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return -1;
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}
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} else {
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if(avctx->max_prediction_order > MAX_FIXED_ORDER) {
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av_log(avctx, AV_LOG_ERROR, "invalid max prediction order: %d\n",
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avctx->max_prediction_order);
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return -1;
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}
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}
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s->options.max_prediction_order = avctx->max_prediction_order;
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}
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if(s->options.max_prediction_order < s->options.min_prediction_order) {
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av_log(avctx, AV_LOG_ERROR, "invalid prediction orders: min=%d max=%d\n",
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s->options.min_prediction_order, s->options.max_prediction_order);
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return -1;
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}
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av_log(avctx, AV_LOG_DEBUG, " prediction order: %d, %d\n",
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s->options.min_prediction_order, s->options.max_prediction_order);
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if(avctx->prediction_order_method >= 0) {
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if(avctx->prediction_order_method > ORDER_METHOD_SEARCH) {
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av_log(avctx, AV_LOG_ERROR, "invalid prediction order method: %d\n",
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avctx->prediction_order_method);
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return -1;
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}
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s->options.prediction_order_method = avctx->prediction_order_method;
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}
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switch(avctx->prediction_order_method) {
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case ORDER_METHOD_EST: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
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"estimate"); break;
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case ORDER_METHOD_2LEVEL: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
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"2-level"); break;
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case ORDER_METHOD_4LEVEL: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
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"4-level"); break;
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case ORDER_METHOD_8LEVEL: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
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"8-level"); break;
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case ORDER_METHOD_SEARCH: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
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"full search"); break;
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}
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if(avctx->min_partition_order >= 0) {
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if(avctx->min_partition_order > MAX_PARTITION_ORDER) {
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av_log(avctx, AV_LOG_ERROR, "invalid min partition order: %d\n",
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avctx->min_partition_order);
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return -1;
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}
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s->options.min_partition_order = avctx->min_partition_order;
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}
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if(avctx->max_partition_order >= 0) {
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if(avctx->max_partition_order > MAX_PARTITION_ORDER) {
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av_log(avctx, AV_LOG_ERROR, "invalid max partition order: %d\n",
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avctx->max_partition_order);
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return -1;
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}
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s->options.max_partition_order = avctx->max_partition_order;
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}
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if(s->options.max_partition_order < s->options.min_partition_order) {
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av_log(avctx, AV_LOG_ERROR, "invalid partition orders: min=%d max=%d\n",
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s->options.min_partition_order, s->options.max_partition_order);
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return -1;
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}
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av_log(avctx, AV_LOG_DEBUG, " partition order: %d, %d\n",
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s->options.min_partition_order, s->options.max_partition_order);
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if(avctx->frame_size > 0) {
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if(avctx->frame_size < FLAC_MIN_BLOCKSIZE ||
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avctx->frame_size > FLAC_MIN_BLOCKSIZE) {
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av_log(avctx, AV_LOG_ERROR, "invalid block size: %d\n",
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avctx->frame_size);
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return -1;
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}
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s->blocksize = avctx->frame_size;
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} else {
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s->blocksize = select_blocksize(s->samplerate, s->options.block_time_ms);
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avctx->frame_size = s->blocksize;
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}
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av_log(avctx, AV_LOG_DEBUG, " block size: %d\n", s->blocksize);
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/* set LPC precision */
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if(avctx->lpc_coeff_precision > 0) {
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if(avctx->lpc_coeff_precision > MAX_LPC_PRECISION) {
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av_log(avctx, AV_LOG_ERROR, "invalid lpc coeff precision: %d\n",
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avctx->lpc_coeff_precision);
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return -1;
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}
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s->options.lpc_coeff_precision = avctx->lpc_coeff_precision;
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} else {
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/* select LPC precision based on block size */
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if( s->blocksize <= 192) s->options.lpc_coeff_precision = 7;
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else if(s->blocksize <= 384) s->options.lpc_coeff_precision = 8;
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else if(s->blocksize <= 576) s->options.lpc_coeff_precision = 9;
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else if(s->blocksize <= 1152) s->options.lpc_coeff_precision = 10;
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else if(s->blocksize <= 2304) s->options.lpc_coeff_precision = 11;
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else if(s->blocksize <= 4608) s->options.lpc_coeff_precision = 12;
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else if(s->blocksize <= 8192) s->options.lpc_coeff_precision = 13;
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else if(s->blocksize <= 16384) s->options.lpc_coeff_precision = 14;
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else s->options.lpc_coeff_precision = 15;
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}
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av_log(avctx, AV_LOG_DEBUG, " lpc precision: %d\n",
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s->options.lpc_coeff_precision);
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/* set maximum encoded frame size in verbatim mode */
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if(s->channels == 2) {
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@ -259,14 +477,13 @@ static void copy_samples(FlacEncodeContext *s, int16_t *samples)
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static int find_optimal_param(uint32_t sum, int n)
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{
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int k, k_opt;
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uint32_t nbits, nbits_opt;
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uint32_t nbits[MAX_RICE_PARAM+1];
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k_opt = 0;
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nbits_opt = rice_encode_count(sum, n, 0);
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for(k=1; k<=14; k++) {
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nbits = rice_encode_count(sum, n, k);
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if(nbits < nbits_opt) {
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nbits_opt = nbits;
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nbits[0] = UINT32_MAX;
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for(k=0; k<=MAX_RICE_PARAM; k++) {
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nbits[k] = rice_encode_count(sum, n, k);
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if(nbits[k] < nbits[k_opt]) {
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k_opt = k;
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}
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}
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@ -297,8 +514,8 @@ static uint32_t calc_optimal_rice_params(RiceContext *rc, int porder,
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return all_bits;
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}
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static void calc_sums(int pmax, uint32_t *data, int n, int pred_order,
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uint32_t sums[][256])
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static void calc_sums(int pmin, int pmax, uint32_t *data, int n, int pred_order,
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uint32_t sums[][MAX_PARTITIONS])
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{
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int i, j;
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int parts;
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@ -316,7 +533,7 @@ static void calc_sums(int pmax, uint32_t *data, int n, int pred_order,
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res_end+= n >> pmax;
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}
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/* sums for lower levels */
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for(i=pmax-1; i>=0; i--) {
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for(i=pmax-1; i>=pmin; i--) {
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parts = (1 << i);
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for(j=0; j<parts; j++) {
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sums[i][j] = sums[i+1][2*j] + sums[i+1][2*j+1];
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@ -324,59 +541,262 @@ static void calc_sums(int pmax, uint32_t *data, int n, int pred_order,
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}
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}
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static uint32_t calc_rice_params(RiceContext *rc, int pmax, int32_t *data,
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int n, int pred_order)
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static uint32_t calc_rice_params(RiceContext *rc, int pmin, int pmax,
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int32_t *data, int n, int pred_order)
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{
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int i;
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uint32_t bits, opt_bits;
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uint32_t bits[MAX_PARTITION_ORDER+1];
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int opt_porder;
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RiceContext opt_rc;
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RiceContext tmp_rc;
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uint32_t *udata;
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uint32_t sums[9][256];
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uint32_t sums[MAX_PARTITION_ORDER+1][MAX_PARTITIONS];
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assert(pmax >= 0 && pmax <= 8);
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assert(pmin >= 0 && pmin <= MAX_PARTITION_ORDER);
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assert(pmax >= 0 && pmax <= MAX_PARTITION_ORDER);
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assert(pmin <= pmax);
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udata = av_malloc(n * sizeof(uint32_t));
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for(i=0; i<n; i++) {
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udata[i] = (2*data[i]) ^ (data[i]>>31);
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}
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calc_sums(pmax, udata, n, pred_order, sums);
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calc_sums(pmin, pmax, udata, n, pred_order, sums);
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opt_porder = 0;
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opt_bits = UINT32_MAX;
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for(i=0; i<=pmax; i++) {
|
||||
bits = calc_optimal_rice_params(rc, i, sums[i], n, pred_order);
|
||||
if(bits < opt_bits) {
|
||||
opt_bits = bits;
|
||||
opt_porder = pmin;
|
||||
bits[pmin] = UINT32_MAX;
|
||||
for(i=pmin; i<=pmax; i++) {
|
||||
bits[i] = calc_optimal_rice_params(&tmp_rc, i, sums[i], n, pred_order);
|
||||
if(bits[i] <= bits[opt_porder]) {
|
||||
opt_porder = i;
|
||||
memcpy(&opt_rc, rc, sizeof(RiceContext));
|
||||
memcpy(rc, &tmp_rc, sizeof(RiceContext));
|
||||
}
|
||||
}
|
||||
if(opt_porder != pmax) {
|
||||
memcpy(rc, &opt_rc, sizeof(RiceContext));
|
||||
}
|
||||
|
||||
av_freep(&udata);
|
||||
return opt_bits;
|
||||
return bits[opt_porder];
|
||||
}
|
||||
|
||||
static uint32_t calc_rice_params_fixed(RiceContext *rc, int pmax, int32_t *data,
|
||||
int n, int pred_order, int bps)
|
||||
static uint32_t calc_rice_params_fixed(RiceContext *rc, int pmin, int pmax,
|
||||
int32_t *data, int n, int pred_order,
|
||||
int bps)
|
||||
{
|
||||
uint32_t bits;
|
||||
bits = pred_order*bps + 6;
|
||||
bits += calc_rice_params(rc, pmax, data, n, pred_order);
|
||||
bits += calc_rice_params(rc, pmin, pmax, data, n, pred_order);
|
||||
return bits;
|
||||
}
|
||||
|
||||
static uint32_t calc_rice_params_lpc(RiceContext *rc, int pmin, int pmax,
|
||||
int32_t *data, int n, int pred_order,
|
||||
int bps, int precision)
|
||||
{
|
||||
uint32_t bits;
|
||||
bits = pred_order*bps + 4 + 5 + pred_order*precision + 6;
|
||||
bits += calc_rice_params(rc, pmin, pmax, data, n, pred_order);
|
||||
return bits;
|
||||
}
|
||||
|
||||
/**
|
||||
* Apply Welch window function to audio block
|
||||
*/
|
||||
static void apply_welch_window(const int32_t *data, int len, double *w_data)
|
||||
{
|
||||
int i, n2;
|
||||
double w;
|
||||
double c;
|
||||
|
||||
n2 = (len >> 1);
|
||||
c = 2.0 / (len - 1.0);
|
||||
for(i=0; i<n2; i++) {
|
||||
w = c - i - 1.0;
|
||||
w = 1.0 - (w * w);
|
||||
w_data[i] = data[i] * w;
|
||||
w_data[len-1-i] = data[len-1-i] * w;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Calculates autocorrelation data from audio samples
|
||||
* A Welch window function is applied before calculation.
|
||||
*/
|
||||
static void compute_autocorr(const int32_t *data, int len, int lag,
|
||||
double *autoc)
|
||||
{
|
||||
int i;
|
||||
double *data1;
|
||||
int lag_ptr, ptr;
|
||||
|
||||
data1 = av_malloc(len * sizeof(double));
|
||||
apply_welch_window(data, len, data1);
|
||||
|
||||
for(i=0; i<lag; i++) autoc[i] = 1.0;
|
||||
|
||||
ptr = 0;
|
||||
while(ptr <= lag) {
|
||||
lag_ptr = 0;
|
||||
while(lag_ptr <= ptr) {
|
||||
autoc[ptr-lag_ptr] += data1[ptr] * data1[lag_ptr];
|
||||
lag_ptr++;
|
||||
}
|
||||
ptr++;
|
||||
}
|
||||
while(ptr < len) {
|
||||
lag_ptr = ptr - lag;
|
||||
while(lag_ptr <= ptr) {
|
||||
autoc[ptr-lag_ptr] += data1[ptr] * data1[lag_ptr];
|
||||
lag_ptr++;
|
||||
}
|
||||
ptr++;
|
||||
}
|
||||
|
||||
av_freep(&data1);
|
||||
}
|
||||
|
||||
/**
|
||||
* Levinson-Durbin recursion.
|
||||
* Produces LPC coefficients from autocorrelation data.
|
||||
*/
|
||||
static void compute_lpc_coefs(const double *autoc, int max_order,
|
||||
double lpc[][MAX_LPC_ORDER], double *ref)
|
||||
{
|
||||
int i, j, i2;
|
||||
double r, err, tmp;
|
||||
double lpc_tmp[MAX_LPC_ORDER];
|
||||
|
||||
for(i=0; i<max_order; i++) lpc_tmp[i] = 0;
|
||||
err = autoc[0];
|
||||
|
||||
for(i=0; i<max_order; i++) {
|
||||
r = -autoc[i+1];
|
||||
for(j=0; j<i; j++) {
|
||||
r -= lpc_tmp[j] * autoc[i-j];
|
||||
}
|
||||
r /= err;
|
||||
ref[i] = fabs(r);
|
||||
|
||||
err *= 1.0 - (r * r);
|
||||
|
||||
i2 = (i >> 1);
|
||||
lpc_tmp[i] = r;
|
||||
for(j=0; j<i2; j++) {
|
||||
tmp = lpc_tmp[j];
|
||||
lpc_tmp[j] += r * lpc_tmp[i-1-j];
|
||||
lpc_tmp[i-1-j] += r * tmp;
|
||||
}
|
||||
if(i & 1) {
|
||||
lpc_tmp[j] += lpc_tmp[j] * r;
|
||||
}
|
||||
|
||||
for(j=0; j<=i; j++) {
|
||||
lpc[i][j] = -lpc_tmp[j];
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Quantize LPC coefficients
|
||||
*/
|
||||
static void quantize_lpc_coefs(double *lpc_in, int order, int precision,
|
||||
int32_t *lpc_out, int *shift)
|
||||
{
|
||||
int i;
|
||||
double d, cmax;
|
||||
int32_t qmax;
|
||||
int sh;
|
||||
|
||||
/* define maximum levels */
|
||||
qmax = (1 << (precision - 1)) - 1;
|
||||
|
||||
/* find maximum coefficient value */
|
||||
cmax = 0.0;
|
||||
for(i=0; i<order; i++) {
|
||||
d = lpc_in[i];
|
||||
if(d < 0) d = -d;
|
||||
if(d > cmax)
|
||||
cmax = d;
|
||||
}
|
||||
|
||||
/* if maximum value quantizes to zero, return all zeros */
|
||||
if(cmax * (1 << MAX_LPC_SHIFT) < 1.0) {
|
||||
*shift = 0;
|
||||
for(i=0; i<order; i++) {
|
||||
lpc_out[i] = 0;
|
||||
}
|
||||
return;
|
||||
}
|
||||
|
||||
/* calculate level shift which scales max coeff to available bits */
|
||||
sh = MAX_LPC_SHIFT;
|
||||
while((cmax * (1 << sh) > qmax) && (sh > 0)) {
|
||||
sh--;
|
||||
}
|
||||
|
||||
/* since negative shift values are unsupported in decoder, scale down
|
||||
coefficients instead */
|
||||
if(sh == 0 && cmax > qmax) {
|
||||
double scale = ((double)qmax) / cmax;
|
||||
for(i=0; i<order; i++) {
|
||||
lpc_in[i] *= scale;
|
||||
}
|
||||
}
|
||||
|
||||
/* output quantized coefficients and level shift */
|
||||
for(i=0; i<order; i++) {
|
||||
lpc_out[i] = (int32_t)(lpc_in[i] * (1 << sh));
|
||||
}
|
||||
*shift = sh;
|
||||
}
|
||||
|
||||
static int estimate_best_order(double *ref, int max_order)
|
||||
{
|
||||
int i, est;
|
||||
|
||||
est = 1;
|
||||
for(i=max_order-1; i>=0; i--) {
|
||||
if(ref[i] > 0.10) {
|
||||
est = i+1;
|
||||
break;
|
||||
}
|
||||
}
|
||||
return est;
|
||||
}
|
||||
|
||||
/**
|
||||
* Calculate LPC coefficients for multiple orders
|
||||
*/
|
||||
static int lpc_calc_coefs(const int32_t *samples, int blocksize, int max_order,
|
||||
int precision, int32_t coefs[][MAX_LPC_ORDER],
|
||||
int *shift)
|
||||
{
|
||||
double autoc[MAX_LPC_ORDER+1];
|
||||
double ref[MAX_LPC_ORDER];
|
||||
double lpc[MAX_LPC_ORDER][MAX_LPC_ORDER];
|
||||
int i;
|
||||
int opt_order;
|
||||
|
||||
assert(max_order >= MIN_LPC_ORDER && max_order <= MAX_LPC_ORDER);
|
||||
|
||||
compute_autocorr(samples, blocksize, max_order+1, autoc);
|
||||
|
||||
compute_lpc_coefs(autoc, max_order, lpc, ref);
|
||||
|
||||
opt_order = estimate_best_order(ref, max_order);
|
||||
|
||||
i = opt_order-1;
|
||||
quantize_lpc_coefs(lpc[i], i+1, precision, coefs[i], &shift[i]);
|
||||
|
||||
return opt_order;
|
||||
}
|
||||
|
||||
|
||||
static void encode_residual_verbatim(int32_t *res, int32_t *smp, int n)
|
||||
{
|
||||
assert(n > 0);
|
||||
memcpy(res, smp, n * sizeof(int32_t));
|
||||
}
|
||||
|
||||
static void encode_residual_fixed(int32_t *res, int32_t *smp, int n, int order)
|
||||
static void encode_residual_fixed(int32_t *res, const int32_t *smp, int n,
|
||||
int order)
|
||||
{
|
||||
int i;
|
||||
|
||||
@ -402,6 +822,24 @@ static void encode_residual_fixed(int32_t *res, int32_t *smp, int n, int order)
|
||||
}
|
||||
}
|
||||
|
||||
static void encode_residual_lpc(int32_t *res, const int32_t *smp, int n,
|
||||
int order, const int32_t *coefs, int shift)
|
||||
{
|
||||
int i, j;
|
||||
int32_t pred;
|
||||
|
||||
for(i=0; i<order; i++) {
|
||||
res[i] = smp[i];
|
||||
}
|
||||
for(i=order; i<n; i++) {
|
||||
pred = 0;
|
||||
for(j=0; j<order; j++) {
|
||||
pred += coefs[j] * smp[i-j-1];
|
||||
}
|
||||
res[i] = smp[i] - (pred >> shift);
|
||||
}
|
||||
}
|
||||
|
||||
static int get_max_p_order(int max_porder, int n, int order)
|
||||
{
|
||||
int porder, max_parts;
|
||||
@ -419,10 +857,13 @@ static int get_max_p_order(int max_porder, int n, int order)
|
||||
|
||||
static int encode_residual(FlacEncodeContext *ctx, int ch)
|
||||
{
|
||||
int i, opt_order, porder, max_porder, n;
|
||||
int i, n;
|
||||
int min_order, max_order, opt_order, precision;
|
||||
int porder, min_porder, max_porder;
|
||||
FlacFrame *frame;
|
||||
FlacSubframe *sub;
|
||||
uint32_t bits[5];
|
||||
int32_t coefs[MAX_LPC_ORDER][MAX_LPC_ORDER];
|
||||
int shift[MAX_LPC_ORDER];
|
||||
int32_t *res, *smp;
|
||||
|
||||
frame = &ctx->frame;
|
||||
@ -448,28 +889,51 @@ static int encode_residual(FlacEncodeContext *ctx, int ch)
|
||||
return sub->obits * n;
|
||||
}
|
||||
|
||||
max_porder = 3;
|
||||
min_order = ctx->options.min_prediction_order;
|
||||
max_order = ctx->options.max_prediction_order;
|
||||
min_porder = ctx->options.min_partition_order;
|
||||
max_porder = ctx->options.max_partition_order;
|
||||
precision = ctx->options.lpc_coeff_precision;
|
||||
|
||||
/* FIXED */
|
||||
opt_order = 0;
|
||||
bits[0] = UINT32_MAX;
|
||||
for(i=0; i<=4; i++) {
|
||||
encode_residual_fixed(res, smp, n, i);
|
||||
porder = get_max_p_order(max_porder, n, i);
|
||||
bits[i] = calc_rice_params_fixed(&sub->rc, porder, res, n, i, sub->obits);
|
||||
if(bits[i] < bits[opt_order]) {
|
||||
opt_order = i;
|
||||
if(!ctx->options.use_lpc || max_order == 0 || (n <= max_order)) {
|
||||
uint32_t bits[MAX_FIXED_ORDER+1];
|
||||
if(max_order > MAX_FIXED_ORDER) max_order = MAX_FIXED_ORDER;
|
||||
opt_order = 0;
|
||||
bits[0] = UINT32_MAX;
|
||||
for(i=min_order; i<=max_order; i++) {
|
||||
encode_residual_fixed(res, smp, n, i);
|
||||
porder = get_max_p_order(max_porder, n, i);
|
||||
bits[i] = calc_rice_params_fixed(&sub->rc, min_porder, porder, res,
|
||||
n, i, sub->obits);
|
||||
if(bits[i] < bits[opt_order]) {
|
||||
opt_order = i;
|
||||
}
|
||||
}
|
||||
sub->order = opt_order;
|
||||
sub->type = FLAC_SUBFRAME_FIXED;
|
||||
sub->type_code = sub->type | sub->order;
|
||||
if(sub->order != max_order) {
|
||||
encode_residual_fixed(res, smp, n, sub->order);
|
||||
porder = get_max_p_order(max_porder, n, sub->order);
|
||||
return calc_rice_params_fixed(&sub->rc, min_porder, porder, res, n,
|
||||
sub->order, sub->obits);
|
||||
}
|
||||
return bits[sub->order];
|
||||
}
|
||||
sub->order = opt_order;
|
||||
sub->type = FLAC_SUBFRAME_FIXED;
|
||||
sub->type_code = sub->type | sub->order;
|
||||
if(sub->order != 4) {
|
||||
encode_residual_fixed(res, smp, n, sub->order);
|
||||
porder = get_max_p_order(max_porder, n, sub->order);
|
||||
calc_rice_params_fixed(&sub->rc, porder, res, n, sub->order, sub->obits);
|
||||
|
||||
/* LPC */
|
||||
sub->order = lpc_calc_coefs(smp, n, max_order, precision, coefs, shift);
|
||||
sub->type = FLAC_SUBFRAME_LPC;
|
||||
sub->type_code = sub->type | (sub->order-1);
|
||||
sub->shift = shift[sub->order-1];
|
||||
for(i=0; i<sub->order; i++) {
|
||||
sub->coefs[i] = coefs[sub->order-1][i];
|
||||
}
|
||||
return bits[sub->order];
|
||||
porder = get_max_p_order(max_porder, n, sub->order);
|
||||
encode_residual_lpc(res, smp, n, sub->order, sub->coefs, sub->shift);
|
||||
return calc_rice_params_lpc(&sub->rc, 0, porder, res, n, sub->order,
|
||||
sub->obits, precision);
|
||||
}
|
||||
|
||||
static int encode_residual_v(FlacEncodeContext *ctx, int ch)
|
||||
@ -509,7 +973,7 @@ static int estimate_stereo_mode(int32_t *left_ch, int32_t *right_ch, int n)
|
||||
uint64_t score[4];
|
||||
int k;
|
||||
|
||||
/* calculate sum of squares for each channel */
|
||||
/* calculate sum of 2nd order residual for each channel */
|
||||
sum[0] = sum[1] = sum[2] = sum[3] = 0;
|
||||
for(i=2; i<n; i++) {
|
||||
lt = left_ch[i] - 2*left_ch[i-1] + left_ch[i-2];
|
||||
@ -519,6 +983,7 @@ static int estimate_stereo_mode(int32_t *left_ch, int32_t *right_ch, int n)
|
||||
sum[0] += ABS(lt);
|
||||
sum[1] += ABS(rt);
|
||||
}
|
||||
/* estimate bit counts */
|
||||
for(i=0; i<4; i++) {
|
||||
k = find_optimal_param(2*sum[i], n);
|
||||
sum[i] = rice_encode_count(2*sum[i], n, k);
|
||||
@ -731,6 +1196,32 @@ static void output_subframe_fixed(FlacEncodeContext *ctx, int ch)
|
||||
output_residual(ctx, ch);
|
||||
}
|
||||
|
||||
static void output_subframe_lpc(FlacEncodeContext *ctx, int ch)
|
||||
{
|
||||
int i, cbits;
|
||||
FlacFrame *frame;
|
||||
FlacSubframe *sub;
|
||||
|
||||
frame = &ctx->frame;
|
||||
sub = &frame->subframes[ch];
|
||||
|
||||
/* warm-up samples */
|
||||
for(i=0; i<sub->order; i++) {
|
||||
put_sbits(&ctx->pb, sub->obits, sub->residual[i]);
|
||||
}
|
||||
|
||||
/* LPC coefficients */
|
||||
cbits = ctx->options.lpc_coeff_precision;
|
||||
put_bits(&ctx->pb, 4, cbits-1);
|
||||
put_sbits(&ctx->pb, 5, sub->shift);
|
||||
for(i=0; i<sub->order; i++) {
|
||||
put_sbits(&ctx->pb, cbits, sub->coefs[i]);
|
||||
}
|
||||
|
||||
/* residual */
|
||||
output_residual(ctx, ch);
|
||||
}
|
||||
|
||||
static void output_subframes(FlacEncodeContext *s)
|
||||
{
|
||||
FlacFrame *frame;
|
||||
@ -754,6 +1245,8 @@ static void output_subframes(FlacEncodeContext *s)
|
||||
output_subframe_verbatim(s, ch);
|
||||
} else if(sub->type == FLAC_SUBFRAME_FIXED) {
|
||||
output_subframe_fixed(s, ch);
|
||||
} else if(sub->type == FLAC_SUBFRAME_LPC) {
|
||||
output_subframe_lpc(s, ch);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
@ -744,6 +744,14 @@ static AVOption options[]={
|
||||
{"mv0_threshold", NULL, OFFSET(mv0_threshold), FF_OPT_TYPE_INT, 256, 0, INT_MAX, V|E},
|
||||
{"ivlc", "intra vlc table", 0, FF_OPT_TYPE_CONST, CODEC_FLAG2_INTRA_VLC, INT_MIN, INT_MAX, V|E, "flags2"},
|
||||
{"b_sensitivity", NULL, OFFSET(b_sensitivity), FF_OPT_TYPE_INT, 40, 1, INT_MAX, V|E},
|
||||
{"compression_level", NULL, OFFSET(compression_level), FF_OPT_TYPE_INT, FF_COMPRESSION_DEFAULT, INT_MIN, INT_MAX, V|A|E},
|
||||
{"use_lpc", NULL, OFFSET(use_lpc), FF_OPT_TYPE_INT, -1, INT_MIN, INT_MAX, A|E},
|
||||
{"lpc_coeff_precision", NULL, OFFSET(lpc_coeff_precision), FF_OPT_TYPE_INT, DEFAULT, 0, INT_MAX, A|E},
|
||||
{"min_prediction_order", NULL, OFFSET(min_prediction_order), FF_OPT_TYPE_INT, -1, INT_MIN, INT_MAX, A|E},
|
||||
{"max_prediction_order", NULL, OFFSET(max_prediction_order), FF_OPT_TYPE_INT, -1, INT_MIN, INT_MAX, A|E},
|
||||
{"prediction_order_method", NULL, OFFSET(prediction_order_method), FF_OPT_TYPE_INT, -1, INT_MIN, INT_MAX, A|E},
|
||||
{"min_partition_order", NULL, OFFSET(min_partition_order), FF_OPT_TYPE_INT, -1, INT_MIN, INT_MAX, A|E},
|
||||
{"max_partition_order", NULL, OFFSET(max_partition_order), FF_OPT_TYPE_INT, -1, INT_MIN, INT_MAX, A|E},
|
||||
{NULL},
|
||||
};
|
||||
|
||||
@ -800,6 +808,13 @@ void avcodec_get_context_defaults(AVCodecContext *s){
|
||||
s->sample_fmt= SAMPLE_FMT_S16; // FIXME: set to NONE
|
||||
s->mv0_threshold= 256;
|
||||
s->b_sensitivity= 40;
|
||||
s->compression_level = FF_COMPRESSION_DEFAULT;
|
||||
s->use_lpc = -1;
|
||||
s->min_prediction_order = -1;
|
||||
s->max_prediction_order = -1;
|
||||
s->prediction_order_method = -1;
|
||||
s->min_partition_order = -1;
|
||||
s->max_partition_order = -1;
|
||||
|
||||
s->intra_quant_bias= FF_DEFAULT_QUANT_BIAS;
|
||||
s->inter_quant_bias= FF_DEFAULT_QUANT_BIAS;
|
||||
|
||||
@ -176,7 +176,7 @@ stddev:1050.18 PSNR:35.89 bytes:1054720
|
||||
264236 ./data/a-adpcm_yam.wav
|
||||
e92cec8c07913ffb91ad2b11f79cdc00 *./data/out.wav
|
||||
stddev:18312.68 PSNR:11.06 bytes:1056768
|
||||
9ab5f311b70bc1fa8591b891db50b386 *./data/a-flac.flac
|
||||
353384 ./data/a-flac.flac
|
||||
c3382f03ce2efb5d475240d288a33898 *./data/a-flac.flac
|
||||
353368 ./data/a-flac.flac
|
||||
c4228df189aad9567a037727d0e763e4 *./data/out.wav
|
||||
stddev: 33.31 PSNR:65.87 bytes:1040384
|
||||
|
||||
@ -599,7 +599,7 @@ fi
|
||||
if [ -n "$do_flac" ] ; then
|
||||
# encoding
|
||||
file=${outfile}flac.flac
|
||||
do_ffmpeg $file -y -ab 128 -ac 2 -ar 44100 -f s16le -i $pcm_src -acodec flac $file
|
||||
do_ffmpeg $file -y -ab 128 -ac 2 -ar 44100 -f s16le -i $pcm_src -acodec flac -compression_level 2 $file
|
||||
|
||||
# decoding
|
||||
do_ffmpeg $pcm_dst -y -i $file -f wav $pcm_dst
|
||||
|
||||
@ -176,7 +176,7 @@ stddev:1050.18 PSNR:35.89 bytes:1054720
|
||||
264236 ./data/a-adpcm_yam.wav
|
||||
e92cec8c07913ffb91ad2b11f79cdc00 *./data/out.wav
|
||||
stddev:18312.68 PSNR:11.06 bytes:1056768
|
||||
9ab5f311b70bc1fa8591b891db50b386 *./data/a-flac.flac
|
||||
353384 ./data/a-flac.flac
|
||||
c3382f03ce2efb5d475240d288a33898 *./data/a-flac.flac
|
||||
353368 ./data/a-flac.flac
|
||||
c4228df189aad9567a037727d0e763e4 *./data/out.wav
|
||||
stddev: 33.31 PSNR:65.87 bytes:1040384
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user