[FFmpeg-devel] Trans.: a64multienc.c and drawutils.c optimisations

[Michael Niedermayer]

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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