[FFmpeg-devel] Trans.: a64multienc.c and drawutils.c optimisations
yann.lepetitcorps at free.fr
yann.lepetitcorps at free.fr
Wed Dec 28 03:28:02 CET 2011
I have begin the factorization on the dpcm_ima_qt_expand_nibble() func into
libavcodec/adpcm.c
This add a very little array
int adpcm_nibble_diff_step_tab[8] = { 0, 4, 2, 6, 1, 3, 5, 7 };
and factorize the 4 "nibbled diffs" on the adpcm_ima_qt_expand_nibble() func
diff = step >> 3;
if (nibble & 4) diff += step;
if (nibble & 2) diff += step >> 1;
if (nibble & 1) diff += step >> 2;
into one indexation into this array, one addition and one multiply
diff = (adpcm_nibble_diff_step_tab[nibble &0x7]+8) * step;
No tested, the +8 add can certainly to be trivialy added to each entry on the
adpcm_nibble_diff_step_tab[] array ... but the idea is here :)
@+
Yannoo
Selon yann.lepetitcorps at free.fr:
> I think that needed modifications are in this attachment
>
> How can I automaticaly replace tabs with the good group of spaces with git
> (or
> gedit) ?
>
> I think to make tomorrow some modifications into the libavcodec/admpc.c file
> at
> the adpcm_ima_qt_expand_nibble() func
> (the 3x diff successives test/additions can certainly to be factorised via a
> multiplication of step with an entry on a table indexed by nibble)
>
>
> @+
> Yannoo
>
> Selon Michael Niedermayer <michaelni at gmx.at>:
>
> > On Tue, Dec 27, 2011 at 09:39:19PM +0100, yann.lepetitcorps at free.fr wrote:
> > > The same thing but with a very little optimization that economize one
> > > multiplication into the memcpy on the memset_sized() func in drawutils.C
> > >
> > > @+
> > > Yannoo
> > >
> > > Selon yann.lepetitcorps at free.fr:
> > >
> > > > I have download the FFMPEG git into my linux box, make modifications,
> > > > compiled
> > > > the new version and generated the diff file in attachment.
> > > >
> > > >
> > > >
> > > > @+
> > > > Yannoo
> > > >
> > > >
> > > > Selon yann.lepetitcorps at free.fr:
> > > >
> > > > > No problem :)
> > > > >
> > > > > => I download the current git head on my linux box and work only with
> > it
> > > > > (instead the 0.9 version that I have previously used on my Apple
> > box)
> > > > >
> > > > > @+
> > > > > Yannoo
> > > > >
> > > > > Selon Carl Eugen Hoyos <cehoyos at ag.or.at>:
> > > > >
> > > > > > <yann.lepetitcorps <at> free.fr> writes:
> > > > > >
> > > > > > > I have begin to analyse FFMPEG 0.9 sources and think to has found
> > somes
> > > > > > areas
> > > > > >
> > > > > > Please do not work on a release, only develop with current git
> head!
> > > > > >
> > > > > > > that can to be a little optimised such as in a64multienc.c or
> > > > drawutils.c
> > > > > >
> > > > > > If you feel unable to use git send-email (which is the preferred
> way
> > of
> > > > > > sending
> > > > > > patches), please at least do "git diff >patchfile.diff" and send
> the
> > > > result
> > > > > > as
> > > > > > an attachment.
> > > > > >
> > > > > > Carl Eugen
> > > > > >
> > > > > > _______________________________________________
> > > > > > ffmpeg-devel mailing list
> > > > > > ffmpeg-devel at ffmpeg.org
> > > > > > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
> > > > > >
> > > > >
> > > > >
> > > > > _______________________________________________
> > > > > ffmpeg-devel mailing list
> > > > > ffmpeg-devel at ffmpeg.org
> > > > > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
> > > > >
> > > >
> > > >
> > > >
> > >
> > >
> >
> > > libavcodec/a64multienc.c | 5 ++-
> > > libavfilter/drawutils.c | 61
> > ++++++++++++++++++++++++++++++++++++++++++++++-
> > > libavfilter/drawutils.h | 6 ++++
> > > 3 files changed, 69 insertions(+), 3 deletions(-)
> > > fb09107371ee746b3b3a4ae5a576ad70fc6e71ec ylp_27dec2011_21h19.diff
> > > diff --git a/libavcodec/a64multienc.c b/libavcodec/a64multienc.c
> > > index 5a665d0..b0e7b14 100644
> > > --- a/libavcodec/a64multienc.c
> > > +++ b/libavcodec/a64multienc.c
> > > @@ -49,15 +49,16 @@ static void to_meta_with_crop(AVCodecContext *avctx,
> > AVFrame *p, int *dest)
> > > int height = FFMIN(avctx->height, C64YRES);
> > > int width = FFMIN(avctx->width , C64XRES);
> > > uint8_t *src = p->data[0];
> > > + uint8_t *src2;
> > >
> > > for (blocky = 0; blocky < C64YRES; blocky += 8) {
> > > for (blockx = 0; blockx < C64XRES; blockx += 8) {
> > > for (y = blocky; y < blocky + 8 && y < C64YRES; y++) {
> > > + src2 = src + y * p->linesize[0];
> > > for (x = blockx; x < blockx + 8 && x < C64XRES; x += 2)
> {
> > > if(x < width && y < height) {
> > > /* build average over 2 pixels */
> > > - luma = (src[(x + 0 + y * p->linesize[0])] +
> > > - src[(x + 1 + y * p->linesize[0])]) / 2;
> > > + luma = ((int)(src2[x]) + (int)(src2[x+1])) / 2;
> >
> > the casts are unneeded
> >
> >
> >
> > > /* write blocks as linear data now so they are
> > suitable for elbg */
> > > dest[0] = luma;
> > > }
> > > diff --git a/libavfilter/drawutils.c b/libavfilter/drawutils.c
> > > index bf308a1..055cfd0 100644
> > > --- a/libavfilter/drawutils.c
> > > +++ b/libavfilter/drawutils.c
> > > @@ -38,6 +38,46 @@ int ff_fill_rgba_map(uint8_t *rgba_map, enum
> PixelFormat
> > pix_fmt)
> > > return 0;
> > > }
> > >
> > > +void memset8(char *dst, char *val, int num)
> > > +{
> > > + memset(dst, *val, num);
> > > +}
> >
> > should be static or needs a ff_ prefix to avoid namespace conflicts
> > with other libs
> > also if it has a ff_ prefix / is intended to be used from outside
> > char val seems easier to use than char *val
> >
> >
> > > +
> > > +void memset16(short int *dst, short int *val, int num)
> > > +{
> > > + int i;
> > > + short int set16 = *val;
> >
> > should be int16_t, as short is not guranteed to be 16bit
> >
> >
> > > +
> > > + for(i=0;i<num;i++)
> > > + *dst++ = set16;
> > > +}
> > > +
> > > +void memset32(int *dst, int *val, int num)
> > > +{
> > > + int i;
> > > + int set32 = *val;
> >
> > int32_t
> >
> >
> > > +
> > > + for(i=0;i<num;i++)
> > > + *dst++ = set32;
> > > +}
> > > +
> > > +
> > > +void memset24(char *dst, char *src, int num)
> > > +{
> > > + int i;
> > > +
> > > + for (i = 0; i < num; i++)
> > > + memcpy(dst + i * 3, src, 3);
> > > +}
> > > +
> > > +void memset_sized(char *dst, char *src, int num, int stepsize)
> > > +{
> > > + int i;
> > > +
> > > + for (i = 0; i < num; i++, dst += stepsize)
> > > + memcpy(dst, src, stepsize);
> > > +}
> > > +
> > > int ff_fill_line_with_color(uint8_t *line[4], int pixel_step[4], int w,
> > uint8_t dst_color[4],
> > > enum PixelFormat pix_fmt, uint8_t
> > rgba_color[4],
> > > int *is_packed_rgba, uint8_t
> rgba_map_ptr[4])
> >
> > > @@ -55,8 +95,27 @@ int ff_fill_line_with_color(uint8_t *line[4], int
> > pixel_step[4], int w, uint8_t
> > > dst_color[rgba_map[i]] = rgba_color[i];
> > >
> > > line[0] = av_malloc(w * pixel_step[0]);
> > > - for (i = 0; i < w; i++)
> > > + /* for (i = 0; i < w; i++)
> > > memcpy(line[0] + i * pixel_step[0], dst_color,
> pixel_step[0]);
> > > + */
> >
> > that can be removed entirely
> >
> >
> > > + switch(av_get_bits_per_pixel(pix_desc))
> >
> > tabs are forbidden in git
> >
> >
> >
> > thanks
> >
> > --
> > Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
> >
> > If you think the mosad wants you dead since a long time then you are either
> > wrong or dead since a long time.
> >
>
>
>
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