[FFmpeg-devel] [PATCH] Indeo 5 decoder
Tue Feb 2 11:23:34 CET 2010
On Feb 1, 2010, at 12:49 PM, Kostya wrote:
> On Mon, Feb 01, 2010 at 02:38:33AM -0500, Alexander Strange wrote:
>> On Feb 1, 2010, at 2:17 AM, Kostya wrote:
>> p * 4 + i saves parens.
> using shifts in such case is our tradition, no?
I tried it and gcc (4.2) converts n*4 to n<<2 even with no optimizations. Maybe it's different with larger scales.
>>> + /* select dequant matrix according with plane and band number */
>>> + band1 = &ctx->planes.bands[i];
>>> + band2 = &ctx->planes.bands[i];
>>> + band2->width = band1->width;
>>> + band2->height = band1->height;
>>> + band2->mb_size = band1->mb_size;
>>> + band2->blk_size = band1->blk_size;
>>> + band2->is_halfpel = band1->is_halfpel;
>>> + band2->quant_mat = band1->quant_mat;
>>> + band2->scan = band1->scan;
>>> + band2->inv_transform = band1->inv_transform;
>>> + band2->dc_transform = band1->dc_transform;
>>> + band2->is_2d_trans = band1->is_2d_trans;
>> memcpy them?
> no, they contain buffer pointers
I meant that IVIBandDesc could be reordered so that
memcpy(&band2->width, &band1->width, (char*)&band2->checksum - (char*)&band2->width);
would work instead of all the assignments (where checksum is the next member after is_2d_trans).
But it's actually pretty ugly, so probably not worth it.
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