On Sat, Jun 27, 2009 at 08:25:43PM +0000, Jai Menon wrote:
On Thu, Jun 25, 2009 at 9:51 PM, Michael Niedermayer<michaelni@gmx.at> wrote:
On Wed, Jun 24, 2009 at 05:59:19PM +0000, Jai Menon wrote:
On Wed, Jun 24, 2009 at 3:58 PM, Michael Niedermayer<michaelni@gmx.at> wrote:
On Wed, Jun 24, 2009 at 01:42:08PM +0000, Jai Menon wrote:
On Wed, Jun 24, 2009 at 1:27 PM, Michael Niedermayer<michaelni@gmx.at> wrote:
On Sun, Jun 21, 2009 at 04:35:20PM +0000, Jai Menon wrote: [...] [...] > @@ -806,6 +815,26 @@ > > line += s->picture.linesize[0]; > } > + } else { > + for (; y < tile->comp[0].coord[1][1] - s->image_offset_y; y++) { > + uint16_t *dst; > + x = tile->comp[0].coord[0][0] - s->image_offset_x; > + dst = line + x * s->ncomponents * 2; > + for (; x < tile->comp[0].coord[0][1] - s->image_offset_x; x++) { > + for (compno = 0; compno < s->ncomponents; compno++) {
> + *src[compno] = av_rescale(*src[compno], (1 << 16) - 1, > + (1 << s->cbps[compno]) - 1);
av_rescale is too slow
So just (*src[compno]/((1 << s->cbps[compno]) - 1)) * ((1 << 16) - 1) ?
* is slow / s slower
"src" << C it should be
<possibly dumb question ahead>
I understand that * and / are slower but how can I achieve the same effect with a single <<?
well, not the same but close enough IMHO src<<C or (src<<C) + (src>>(16-C)) should be close enough, my point was mainly that av_rescale() is too slow to be done per pixel and anything else is better
Okay, modified patch attached.
[...]
@@ -806,6 +815,22 @@
line += s->picture.linesize[0]; } + } else { + for (; y < tile->comp[0].coord[1][1] - s->image_offset_y; y++) { + uint16_t *dst; + x = tile->comp[0].coord[0][0] - s->image_offset_x; + dst = line + x * s->ncomponents * 2; + for (; x < tile->comp[0].coord[0][1] - s->image_offset_x; x++) { + for (compno = 0; compno < s->ncomponents; compno++) { + *src[compno] = *src[compno] << (16 - s->cbps[compno]); + *src[compno] += 1 << 15; + *src[compno] = av_clip(*src[compno], 0, (1 << 16) - 1); + *dst++ = *src[compno]++;
i dont think using *src[compno] as a temporary is a good choice [...] -- Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB Opposition brings concord. Out of discord comes the fairest harmony. -- Heraclitus