Mats Peterson <matsp888-at-yahoo....@ffmpeg.org> skrev: (11 mars 2016 14:12:56 CET) >Mats Peterson <matsp888-at-yahoo....@ffmpeg.org> skrev: (11 mars 2016 >14:06:19 CET) >>Mats Peterson <matsp888-at-yahoo....@ffmpeg.org> skrev: (11 mars 2016 >>13:55:20 CET) >>>Michael Niedermayer <mich...@niedermayer.cc> skrev: (11 mars 2016 >>>13:49:32 CET) >>>>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" >>>> >>>> >>>>[...] >>> >>>That's correct. Sorry. Anyway, the only case I know of is HuffYUV >with >>>its special variant of BITMAPINFOHEADER that includes the Huffman >>>tables. Is there stated anywhere in the ASUS specs that the size of >>the >>>extra data following the BITMAPINFOHEADER should be included in >>biSize? >>>If not, it should be 40. >>> >>>Mats >>>-- >>>Mats Peterson >>>http://matsp888.no-ip.org/~mats/ >>>_______________________________________________ >>>ffmpeg-devel mailing list >>>ffmpeg-devel@ffmpeg.org >>>http://ffmpeg.org/mailman/listinfo/ffmpeg-devel >> >>Those asv1/asv2 files play just fine with a biSize of 40, at that. >> >>Mats >>-- >>Mats Peterson >>http://matsp888.no-ip.org/~mats/ >>_______________________________________________ >>ffmpeg-devel mailing list >>ffmpeg-devel@ffmpeg.org >>http://ffmpeg.org/mailman/listinfo/ffmpeg-devel > >Should we perhaps "tighten" the "specs" (I saw that you have written >some documentation on asv1/asv2 in FFmpeg), and include those extra >bytes in biSize? I suppose this is somewhat of a proprietary FFmpeg >invention. > >Mats >-- >Mats Peterson >http://matsp888.no-ip.org/~mats/ >_______________________________________________ >ffmpeg-devel mailing list >ffmpeg-devel@ffmpeg.org >http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
In my book it's totally unnecessary, though, since we already have the size of the global asv1/asv2 header by subtracting the size of the BITMAPINFOHEADER from the strf chunk size. And the files play fine with a biSize of 40. Mats -- Mats Peterson http://matsp888.no-ip.org/~mats/ _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
