Reinhard Nissl wrote: > Hi, > > Christian Gmeiner wrote: > >> i am currently interested in this topic and wanted to know how VDR >> does handle this. If you dont know what AFD is: >> http://www.pjdaniel.org.uk/afd/index.html >> http://www.dtg.org.uk/publications/books/afd.pdf >> >> I think that VDR needs a menuentry where the user must specify what >> kind of tv-set he owns (4:3 or 16:9). >> If we add this we could make use of the AFD header in VDR. Maybe i am >> wrong and AFD is allready supported by VDR. > > > Well, I've added extracting AFD information in xine. But so far, I do > nothing more than storing this information as stream info. Thats a good beginning... > > As far as I can tell, VDR doesn't extract any AFD information from > video streams. But it should not be too complicated to add this to > cRemux::ScanVideoPacket(), due to the repacking of cVideoRepacker. > > AFD information appears in the video stream after user data startcodes > (0x000001B2) and these appear before picture start codes (0x00000100). > Typically, there are only a few bytes between those startcodes. And as > cVideoRepacker ensures a new PES packet for each picture, AFD > information should be in the same 2048 byte block where > ScanVideoPacket() finds the picture start code. > > The next few lines are from xine-lib/src/libmpeg2/decode.c: > > /* check Active Format Description ETSI TS 101 154 V1.5.1 */ > else if (buffer[0] == 0x44 && buffer[1] == 0x54 && buffer[2] == 0x47 > && buffer[3] == 0x31) > { > int afd = (buffer[4] & 0x40) ? (buffer[5] & 0x0f) : -1; > _x_stream_info_set(mpeg2dec->stream, XINE_STREAM_INFO_VIDEO_AFD, afd); > } > > And these are from xine-lib/include/xine.h: > > /* possible values for XINE_STREAM_INFO_VIDEO_AFD */ > #define XINE_VIDEO_AFD_NOT_PRESENT -1 > #define XINE_VIDEO_AFD_RESERVED_0 0 > #define XINE_VIDEO_AFD_RESERVED_1 1 > #define XINE_VIDEO_AFD_BOX_16_9_TOP 2 > #define XINE_VIDEO_AFD_BOX_14_9_TOP 3 > #define XINE_VIDEO_AFD_BOX_GT_16_9_CENTRE 4 > #define XINE_VIDEO_AFD_RESERVED_5 5 > #define XINE_VIDEO_AFD_RESERVED_6 6 > #define XINE_VIDEO_AFD_RESERVED_7 7 > #define XINE_VIDEO_AFD_SAME_AS_FRAME 8 > #define XINE_VIDEO_AFD_4_3_CENTRE 9 > #define XINE_VIDEO_AFD_16_9_CENTRE 10 > #define XINE_VIDEO_AFD_14_9_CENTRE 11 > #define XINE_VIDEO_AFD_RESERVED_12 12 > #define XINE_VIDEO_AFD_4_3_PROTECT_14_9 13 > #define XINE_VIDEO_AFD_16_9_PROTECT_14_9 14 > #define XINE_VIDEO_AFD_16_9_PROTECT_4_3 15 > > But don't expect this feature to be part of VDR-1.4. I dont expect it, but i think it might be very usefull. I come to this topic, becuase there is an patch for the dxr3 plugin and dxr3 driver, which includes such afd header support, but i dont think its the best way to it this way. Also i dont know how dvb driver support such stuff. If they support it, we have a fine base to start wokring on this topic. Greets -- Christian Gmeiner Developer for Rockbox (http://www.rockbox.org) Maintainer of the DXR3-Plugin for VDR: http://sourceforge.net/projects/dxr3plugin/ Maintainer of VDR-Ebuilds at Gentoo.de
