On Fri, Mar 11, 2016 at 01:28:47PM +0100, Mats Peterson wrote: > On 03/11/2016 01:25 PM, Mats Peterson wrote: > >On 03/11/2016 01:14 PM, Michael Niedermayer wrote: > >>On Fri, Mar 11, 2016 at 05:17:18AM +0100, Mats Peterson wrote: > >>>On 03/11/2016 05:10 AM, Mats Peterson wrote: > >>>>Forget patch 2/3 and 3/3 from the old patch set. > >>>> > >>>> From the Microsoft documentation for BITMAPINFOHEADER at > >>>>https://msdn.microsoft.com/en-us/library/windows/desktop/dd318229%28v=vs.85%29.aspx: > >>>> > >>>> > >>>> > >>>>"biSize: Specifies the number of bytes required by the structure. This > >>>>value does not include the size of the color table or the size of the > >>>>color masks, if they are appended to the end of structure." > >>>> > >>>>So, biSize is always 40. Also, Windows Media Player won't detect video > >>>>encoded with Microsoft Video 1 in 8 bpp mode if this value is anything > >>>>else than 40. I don't know about other codecs, they probably work. > >>>>Anyway, we should stick with the specs, and not include the palette > >>>>size > >>>>in that field. > >>>> > >>>>Regarding the biClrUsed field, I'm setting it to 1 << > >>>>bits_per_coded_sample if palettized video, since setting it to 0 is > >>>>another case where it won't work with Windows Media Player and > >>>>Microsoft > >>>>Video 1 in 8 bpp mode. > >>>> > >>>>Mats > >>>> > >>>> > >>>> > >>> > >>>Once, again, HuffYUV has its own variant of BITMAPINFOHEADER that > >>>*does* include the size of the Huffman tables in biSize. That's the > >>>only exception as far as I know. > >> > >>is huffyuv really the exception ? and not raw rgb or palettes ? > >> > >>asv1 and asv2 do not have 40 there
> >>which codec with a non-palette global header puts 40 there ? [...] > As I said before, Microsoft Video 1 in 8-bit mode and RLE4/RLE8 > won't even display in Windows Media Player if this value is anything > else than 40. msv1 / RLE4/8 doesnt have a "Non palette global header" [...] -- Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB Complexity theory is the science of finding the exact solution to an approximation. Benchmarking OTOH is finding an approximation of the exact
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