[FFmpeg-cvslog] Separate window function from autocorrelation.
Justin Ruggles
git
Sun Jan 23 21:01:53 CET 2011
ffmpeg | branch: master | Justin Ruggles <justin.ruggles at gmail.com> | Fri Jan 21 00:12:03 2011 +0000| [7101b1850822c2490cfaf2c5f4addf2ccbf7eab1] | committer: Michael Niedermayer
Separate window function from autocorrelation.
Signed-off-by: Mans Rullgard <mans at mansr.com>
(cherry picked from commit 77a78e9bdcc589efac41da4f92a489f4523667c0)
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=7101b1850822c2490cfaf2c5f4addf2ccbf7eab1
---
libavcodec/alacenc.c | 8 +++++-
libavcodec/flacenc.c | 10 +++++---
libavcodec/lpc.c | 57 +++++++++++++++++++++++++++++++++-------------
libavcodec/lpc.h | 31 ++++++++++++++++++++++--
libavcodec/ra144enc.c | 13 +++++++++-
libavcodec/x86/lpc_mmx.c | 19 +++++----------
6 files changed, 99 insertions(+), 39 deletions(-)
diff --git a/libavcodec/alacenc.c b/libavcodec/alacenc.c
index 5706ae9..d9ff2b8 100644
--- a/libavcodec/alacenc.c
+++ b/libavcodec/alacenc.c
@@ -378,6 +378,7 @@ static void write_compressed_frame(AlacEncodeContext *s)
static av_cold int alac_encode_init(AVCodecContext *avctx)
{
AlacEncodeContext *s = avctx->priv_data;
+ int ret;
uint8_t *alac_extradata = av_mallocz(ALAC_EXTRADATA_SIZE+1);
avctx->frame_size = DEFAULT_FRAME_SIZE;
@@ -455,9 +456,10 @@ static av_cold int alac_encode_init(AVCodecContext *avctx)
avctx->coded_frame->key_frame = 1;
s->avctx = avctx;
- ff_lpc_init(&s->lpc_ctx);
+ ret = ff_lpc_init(&s->lpc_ctx, avctx->frame_size, s->max_prediction_order,
+ AV_LPC_TYPE_LEVINSON);
- return 0;
+ return ret;
}
static int alac_encode_frame(AVCodecContext *avctx, uint8_t *frame,
@@ -513,6 +515,8 @@ verbatim:
static av_cold int alac_encode_close(AVCodecContext *avctx)
{
+ AlacEncodeContext *s = avctx->priv_data;
+ ff_lpc_end(&s->lpc_ctx);
av_freep(&avctx->extradata);
avctx->extradata_size = 0;
av_freep(&avctx->coded_frame);
diff --git a/libavcodec/flacenc.c b/libavcodec/flacenc.c
index d6f0f87..2bfe56e 100644
--- a/libavcodec/flacenc.c
+++ b/libavcodec/flacenc.c
@@ -211,13 +211,11 @@ static av_cold int flac_encode_init(AVCodecContext *avctx)
int freq = avctx->sample_rate;
int channels = avctx->channels;
FlacEncodeContext *s = avctx->priv_data;
- int i, level;
+ int i, level, ret;
uint8_t *streaminfo;
s->avctx = avctx;
- ff_lpc_init(&s->lpc_ctx);
-
if (avctx->sample_fmt != AV_SAMPLE_FMT_S16)
return -1;
@@ -438,9 +436,12 @@ static av_cold int flac_encode_init(AVCodecContext *avctx)
if (!avctx->coded_frame)
return AVERROR(ENOMEM);
+ ret = ff_lpc_init(&s->lpc_ctx, avctx->frame_size,
+ s->options.max_prediction_order, AV_LPC_TYPE_LEVINSON);
+
dprint_compression_options(s);
- return 0;
+ return ret;
}
@@ -1316,6 +1317,7 @@ static av_cold int flac_encode_close(AVCodecContext *avctx)
if (avctx->priv_data) {
FlacEncodeContext *s = avctx->priv_data;
av_freep(&s->md5ctx);
+ ff_lpc_end(&s->lpc_ctx);
}
av_freep(&avctx->extradata);
avctx->extradata_size = 0;
diff --git a/libavcodec/lpc.c b/libavcodec/lpc.c
index 3a93c9f..fd51491 100644
--- a/libavcodec/lpc.c
+++ b/libavcodec/lpc.c
@@ -28,7 +28,7 @@
/**
* Apply Welch window function to audio block
*/
-static void apply_welch_window(const int32_t *data, int len, double *w_data)
+static void apply_welch_window_c(const int32_t *data, int len, double *w_data)
{
int i, n2;
double w;
@@ -54,24 +54,16 @@ static void apply_welch_window(const int32_t *data, int len, double *w_data)
* Calculate autocorrelation data from audio samples
* A Welch window function is applied before calculation.
*/
-static void lpc_compute_autocorr_c(const int32_t *data, int len, int lag,
+static void lpc_compute_autocorr_c(const double *data, int len, int lag,
double *autoc)
{
int i, j;
- double tmp[len + lag + 1];
- double *data1= tmp + lag;
-
- apply_welch_window(data, len, data1);
-
- for(j=0; j<lag; j++)
- data1[j-lag]= 0.0;
- data1[len] = 0.0;
for(j=0; j<lag; j+=2){
double sum0 = 1.0, sum1 = 1.0;
for(i=j; i<len; i++){
- sum0 += data1[i] * data1[i-j];
- sum1 += data1[i] * data1[i-j-1];
+ sum0 += data[i] * data[i-j];
+ sum1 += data[i] * data[i-j-1];
}
autoc[j ] = sum0;
autoc[j+1] = sum1;
@@ -80,8 +72,8 @@ static void lpc_compute_autocorr_c(const int32_t *data, int len, int lag,
if(j==lag){
double sum = 1.0;
for(i=j-1; i<len; i+=2){
- sum += data1[i ] * data1[i-j ]
- + data1[i+1] * data1[i-j+1];
+ sum += data[i ] * data[i-j ]
+ + data[i+1] * data[i-j+1];
}
autoc[j] = sum;
}
@@ -177,8 +169,19 @@ int ff_lpc_calc_coefs(LPCContext *s,
assert(max_order >= MIN_LPC_ORDER && max_order <= MAX_LPC_ORDER &&
lpc_type > AV_LPC_TYPE_FIXED);
+ /* reinit LPC context if parameters have changed */
+ if (blocksize != s->blocksize || max_order != s->max_order ||
+ lpc_type != s->lpc_type) {
+ ff_lpc_end(s);
+ ff_lpc_init(s, blocksize, max_order, lpc_type);
+ }
+
if (lpc_type == AV_LPC_TYPE_LEVINSON) {
- s->lpc_compute_autocorr(samples, blocksize, max_order, autoc);
+ double *windowed_samples = s->windowed_samples + max_order;
+
+ s->lpc_apply_welch_window(samples, blocksize, windowed_samples);
+
+ s->lpc_compute_autocorr(windowed_samples, blocksize, max_order, autoc);
compute_lpc_coefs(autoc, max_order, &lpc[0][0], MAX_LPC_ORDER, 0, 1);
@@ -236,10 +239,32 @@ int ff_lpc_calc_coefs(LPCContext *s,
return opt_order;
}
-av_cold void ff_lpc_init(LPCContext *s)
+av_cold int ff_lpc_init(LPCContext *s, int blocksize, int max_order,
+ enum AVLPCType lpc_type)
{
+ s->blocksize = blocksize;
+ s->max_order = max_order;
+ s->lpc_type = lpc_type;
+
+ if (lpc_type == AV_LPC_TYPE_LEVINSON) {
+ s->windowed_samples = av_mallocz((blocksize + max_order + 2) *
+ sizeof(*s->windowed_samples));
+ if (!s->windowed_samples)
+ return AVERROR(ENOMEM);
+ } else {
+ s->windowed_samples = NULL;
+ }
+
+ s->lpc_apply_welch_window = apply_welch_window_c;
s->lpc_compute_autocorr = lpc_compute_autocorr_c;
if (HAVE_MMX)
ff_lpc_init_x86(s);
+
+ return 0;
+}
+
+av_cold void ff_lpc_end(LPCContext *s)
+{
+ av_freep(&s->windowed_samples);
}
diff --git a/libavcodec/lpc.h b/libavcodec/lpc.h
index a307793..96b66df 100644
--- a/libavcodec/lpc.h
+++ b/libavcodec/lpc.h
@@ -37,16 +37,35 @@
typedef struct LPCContext {
+ int blocksize;
+ int max_order;
+ enum AVLPCType lpc_type;
+ double *windowed_samples;
+
+ /**
+ * Apply a Welch window to an array of input samples.
+ * The output samples have the same scale as the input, but are in double
+ * sample format.
+ * @param data input samples
+ * @param len number of input samples
+ * @param w_data output samples
+ */
+ void (*lpc_apply_welch_window)(const int32_t *data, int len,
+ double *w_data);
/**
* Perform autocorrelation on input samples with delay of 0 to lag.
* @param data input samples.
- * no alignment needed.
+ * constraints: no alignment needed, but must have have at
+ * least lag*sizeof(double) valid bytes preceeding it, and
+ * size must be at least (len+1)*sizeof(double) if data is
+ * 16-byte aligned or (len+2)*sizeof(double) if data is
+ * unaligned.
* @param len number of input samples to process
* @param lag maximum delay to calculate
* @param autoc output autocorrelation coefficients.
* constraints: array size must be at least lag+1.
*/
- void (*lpc_compute_autocorr)(const int32_t *data, int len, int lag,
+ void (*lpc_compute_autocorr)(const double *data, int len, int lag,
double *autoc);
} LPCContext;
@@ -64,9 +83,15 @@ int ff_lpc_calc_coefs(LPCContext *s,
/**
* Initialize LPCContext.
*/
-void ff_lpc_init(LPCContext *s);
+int ff_lpc_init(LPCContext *s, int blocksize, int max_order,
+ enum AVLPCType lpc_type);
void ff_lpc_init_x86(LPCContext *s);
+/**
+ * Uninitialize LPCContext.
+ */
+void ff_lpc_end(LPCContext *s);
+
#ifdef LPC_USE_DOUBLE
#define LPC_TYPE double
#else
diff --git a/libavcodec/ra144enc.c b/libavcodec/ra144enc.c
index 3f8694e..2c0a6b1 100644
--- a/libavcodec/ra144enc.c
+++ b/libavcodec/ra144enc.c
@@ -36,6 +36,7 @@
static av_cold int ra144_encode_init(AVCodecContext * avctx)
{
RA144Context *ractx;
+ int ret;
if (avctx->sample_fmt != AV_SAMPLE_FMT_S16) {
av_log(avctx, AV_LOG_ERROR, "invalid sample format\n");
@@ -52,7 +53,16 @@ static av_cold int ra144_encode_init(AVCodecContext * avctx)
ractx->lpc_coef[0] = ractx->lpc_tables[0];
ractx->lpc_coef[1] = ractx->lpc_tables[1];
ractx->avctx = avctx;
- ff_lpc_init(&ractx->lpc_ctx);
+ ret = ff_lpc_init(&ractx->lpc_ctx, avctx->frame_size, LPC_ORDER,
+ AV_LPC_TYPE_LEVINSON);
+ return ret;
+}
+
+
+static av_cold int ra144_encode_close(AVCodecContext *avctx)
+{
+ RA144Context *ractx = avctx->priv_data;
+ ff_lpc_end(&ractx->lpc_ctx);
return 0;
}
@@ -506,5 +516,6 @@ AVCodec ra_144_encoder =
sizeof(RA144Context),
ra144_encode_init,
ra144_encode_frame,
+ ra144_encode_close,
.long_name = NULL_IF_CONFIG_SMALL("RealAudio 1.0 (14.4K) encoder"),
};
diff --git a/libavcodec/x86/lpc_mmx.c b/libavcodec/x86/lpc_mmx.c
index 19aad98..3a0a1f0 100644
--- a/libavcodec/x86/lpc_mmx.c
+++ b/libavcodec/x86/lpc_mmx.c
@@ -69,21 +69,13 @@ static void apply_welch_window_sse2(const int32_t *data, int len, double *w_data
#undef WELCH
}
-static void lpc_compute_autocorr_sse2(const int32_t *data, int len, int lag,
+static void lpc_compute_autocorr_sse2(const double *data, int len, int lag,
double *autoc)
{
- double tmp[len + lag + 2];
- double *data1 = tmp + lag;
int j;
- if((x86_reg)data1 & 15)
- data1++;
-
- apply_welch_window_sse2(data, len, data1);
-
- for(j=0; j<lag; j++)
- data1[j-lag]= 0.0;
- data1[len] = 0.0;
+ if((x86_reg)data & 15)
+ data++;
for(j=0; j<lag; j+=2){
x86_reg i = -len*sizeof(double);
@@ -114,7 +106,7 @@ static void lpc_compute_autocorr_sse2(const int32_t *data, int len, int lag,
"movsd %%xmm1, 8(%1) \n\t"
"movsd %%xmm2, 16(%1) \n\t"
:"+&r"(i)
- :"r"(autoc+j), "r"(data1+len), "r"(data1+len-j)
+ :"r"(autoc+j), "r"(data+len), "r"(data+len-j)
:"memory"
);
} else {
@@ -137,7 +129,7 @@ static void lpc_compute_autocorr_sse2(const int32_t *data, int len, int lag,
"movsd %%xmm0, %1 \n\t"
"movsd %%xmm1, %2 \n\t"
:"+&r"(i), "=m"(autoc[j]), "=m"(autoc[j+1])
- :"r"(data1+len), "r"(data1+len-j)
+ :"r"(data+len), "r"(data+len-j)
);
}
}
@@ -148,6 +140,7 @@ av_cold void ff_lpc_init_x86(LPCContext *c)
int mm_flags = av_get_cpu_flags();
if (mm_flags & (AV_CPU_FLAG_SSE2|AV_CPU_FLAG_SSE2SLOW)) {
+ c->lpc_apply_welch_window = apply_welch_window_sse2;
c->lpc_compute_autocorr = lpc_compute_autocorr_sse2;
}
}
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