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| author | Jason Garrett-Glaser <darkshikari@gmail.com> | 2010-08-02 20:57:03 +0000 |
|---|---|---|
| committer | Jason Garrett-Glaser <darkshikari@gmail.com> | 2010-08-02 20:57:03 +0000 |
| commit | f311208cf1ebbd74f8a3bd111d9172f41188aa83 (patch) | |
| tree | 6183bd58dae57998d1b8cb1e8fd78b941e1aed95 /libavcodec/vp8dsp.c | |
| parent | c934562c1293167a35a0350358e8b76ec73a3364 (diff) | |
| download | ffmpeg-f311208cf1ebbd74f8a3bd111d9172f41188aa83.tar.gz | |
VP8: much faster DC transform handling
A lot of the time the DC block is empty: don't do the WHT in this case.
A lot of the rest of the time, there's only one coefficient: make a special
DC-only transform for that case.
When the block is empty, don't incorrectly mark luma DCT blocks as having DC
coefficients.
Originally committed as revision 24670 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/vp8dsp.c')
| -rw-r--r-- | libavcodec/vp8dsp.c | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/libavcodec/vp8dsp.c b/libavcodec/vp8dsp.c index 5f5124803d..b8cf0b2f6c 100644 --- a/libavcodec/vp8dsp.c +++ b/libavcodec/vp8dsp.c @@ -51,13 +51,25 @@ static void vp8_luma_dc_wht_c(DCTELEM block[4][4][16], DCTELEM dc[16]) dc[i*4+2] = 0; dc[i*4+3] = 0; - *block[i][0] = (t0 + t1) >> 3; - *block[i][1] = (t3 + t2) >> 3; - *block[i][2] = (t0 - t1) >> 3; - *block[i][3] = (t3 - t2) >> 3; + block[i][0][0] = (t0 + t1) >> 3; + block[i][1][0] = (t3 + t2) >> 3; + block[i][2][0] = (t0 - t1) >> 3; + block[i][3][0] = (t3 - t2) >> 3; } } +static void vp8_luma_dc_wht_dc_c(DCTELEM block[4][4][16], DCTELEM dc[16]) +{ + int i, val = (dc[0] + 3) >> 3; + dc[0] = 0; + + for (i = 0; i < 4; i++) { + block[i][0][0] = val; + block[i][1][0] = val; + block[i][2][0] = val; + block[i][3][0] = val; + } +} #define MUL_20091(a) ((((a)*20091) >> 16) + (a)) #define MUL_35468(a) (((a)*35468) >> 16) @@ -480,6 +492,7 @@ VP8_BILINEAR(4) av_cold void ff_vp8dsp_init(VP8DSPContext *dsp) { dsp->vp8_luma_dc_wht = vp8_luma_dc_wht_c; + dsp->vp8_luma_dc_wht_dc = vp8_luma_dc_wht_dc_c; dsp->vp8_idct_add = vp8_idct_add_c; dsp->vp8_idct_dc_add = vp8_idct_dc_add_c; dsp->vp8_idct_dc_add4y = vp8_idct_dc_add4y_c; |