[FFmpeg-cvslog] r19900 - trunk/libavcodec/atrac1.c
banan
subversion
Thu Sep 17 20:52:11 CEST 2009
Author: banan
Date: Thu Sep 17 20:52:11 2009
New Revision: 19900
Log:
Only use one mdct window size in atrac1.
Modified:
trunk/libavcodec/atrac1.c
Modified: trunk/libavcodec/atrac1.c
==============================================================================
--- trunk/libavcodec/atrac1.c Thu Sep 17 20:46:50 2009 (r19899)
+++ trunk/libavcodec/atrac1.c Thu Sep 17 20:52:11 2009 (r19900)
@@ -73,7 +73,8 @@ typedef struct {
typedef struct {
AT1SUCtx SUs[AT1_MAX_CHANNELS]; ///< channel sound unit
DECLARE_ALIGNED_16(float,spec[AT1_SU_SAMPLES]); ///< the mdct spectrum buffer
- DECLARE_ALIGNED_16(float,short_buf[64]); ///< buffer for the short mode
+ DECLARE_ALIGNED_16(float,short_buf[512]); ///< buffer for the short mode
+
DECLARE_ALIGNED_16(float, low[256]);
DECLARE_ALIGNED_16(float, mid[256]);
DECLARE_ALIGNED_16(float,high[512]);
@@ -84,10 +85,7 @@ typedef struct {
DSPContext dsp;
} AT1Ctx;
-static float *short_window;
-static float *mid_window;
-DECLARE_ALIGNED_16(static float, long_window[256]);
-static float *window_per_band[3];
+DECLARE_ALIGNED_16(static float, short_window[32]);
/** size of the transform in samples in the long mode for each QMF band */
static const uint16_t samples_per_band[3] = {128, 128, 256};
@@ -137,28 +135,37 @@ static int at1_imdct_block(AT1SUCtx* su,
if (num_blocks == 1) {
at1_imdct(q, &q->spec[pos], &su->spectrum[0][ref_pos], nbits, band_num);
pos += block_size; // move to the next mdct block in the spectrum
+
+ /* overlap and window long blocks */
+ q->dsp.vector_fmul_window(q->bands[band_num], &su->spectrum[1][ref_pos+band_samples-16],
+ &su->spectrum[0][ref_pos], short_window, 0, 16);
+ memcpy(q->bands[band_num]+32, &su->spectrum[0][ref_pos+16], 240 * sizeof(float));
+
} else {
/* calc start position for the 1st short block: 96(128) or 112(256) */
+ int short_pos = 32;
+ float *prev_buf;
start_pos = (band_samples * (num_blocks - 1)) >> (log2_block_count + 1);
memset(&su->spectrum[0][ref_pos], 0, sizeof(float) * (band_samples * 2));
+ prev_buf = &su->spectrum[1][ref_pos+band_samples-16];
for (; num_blocks!=0 ; num_blocks--) {
/* use hardcoded nbits for the short mode */
- at1_imdct(q, &q->spec[pos], q->short_buf, 5, band_num);
+ at1_imdct(q, &q->spec[pos], &q->short_buf[short_pos], 5, band_num);
/* overlap and window between short blocks */
q->dsp.vector_fmul_window(&su->spectrum[0][ref_pos+start_pos],
- &su->spectrum[0][ref_pos+start_pos],
- q->short_buf,short_window, 0, 16);
+ &q->short_buf[short_pos-16],
+ &q->short_buf[short_pos],short_window, 0, 16);
+
+ prev_buf = &q->short_buf[short_pos+16];
+
start_pos += 32; // use hardcoded block_size
pos += 32;
+ short_pos +=32;
}
+ memcpy(q->bands[band_num], &su->spectrum[0][ref_pos], band_samples*sizeof(float));
}
-
- /* overlap and window with the previous frame and output the result */
- q->dsp.vector_fmul_window(q->bands[band_num], &su->spectrum[1][ref_pos+band_samples/2],
- &su->spectrum[0][ref_pos], window_per_band[band_num], 0, band_samples/2);
-
ref_pos += band_samples;
}
@@ -331,42 +338,6 @@ static int atrac1_decode_frame(AVCodecCo
}
-static av_cold void init_mdct_windows(void)
-{
- int i;
-
- /** The mid and long windows uses the same sine window splitted
- * in the middle and wrapped into zero/one regions as follows:
- *
- * region of "ones"
- * -------------
- * /
- * / 1st half
- * / of the sine
- * / window
- * ---------/
- * zero region
- *
- * The mid and short windows are subsets of the long window.
- */
-
- /* Build "zero" region */
- memset(long_window, 0, sizeof(long_window));
- /* Build sine window region */
- short_window = &long_window[112];
- ff_sine_window_init(short_window,32);
- /* Build "ones" region */
- for (i = 0; i < 112; i++)
- long_window[144 + i] = 1.0f;
- /* Save the mid window subset start */
- mid_window = &long_window[64];
-
- /* Prepare the window table */
- window_per_band[0] = mid_window;
- window_per_band[1] = mid_window;
- window_per_band[2] = long_window;
-}
-
static av_cold int atrac1_decode_init(AVCodecContext *avctx)
{
AT1Ctx *q = avctx->priv_data;
@@ -379,7 +350,8 @@ static av_cold int atrac1_decode_init(AV
ff_mdct_init(&q->mdct_ctx[0], 6, 1, -1.0/ (1<<15));
ff_mdct_init(&q->mdct_ctx[1], 8, 1, -1.0/ (1<<15));
ff_mdct_init(&q->mdct_ctx[2], 9, 1, -1.0/ (1<<15));
- init_mdct_windows();
+
+ ff_sine_window_init(short_window, 32);
atrac_generate_tables();
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