[mythtv] My ongoing quest for a stable bobdeint setup...
staffan.pettersson at sverige.nu
Wed Feb 23 21:41:13 UTC 2005
> My motivations in this context:
> - I want full field rate in video playback; to my knowledge, using
> bobdeint is the only way to achieve this;
> - bobdeint requires a form of vertical sync, which as far as I know the
> SiS driver cannot support.
> In my ongoing quest to find an X setup that gives me jitter-free video
> using bobdeint I stumbled upon a new option, found on the SiS X driver
> website (http://www.winischhofer.at/linuxsispart1.shtml):
>> *2. Video blitter method*
>> This second method is only supported on the SiS M650, 651, (M)661,
>> (M)741, 330 and (M)760, not any older chipsets. It works entirely
>> different to the overlay method: The video blitter simply copies video
>> data from the video application into the framebuffer (eg. a window),
>> thereby converting the data from the video color space (some YUV
>> format) to RGB. All this is done by the 2D acceleration engine.
>> The following color space formats are supported: YV12, I420, UYVY,
>> YUY2, YVYU, NV12, NV21. The maximum video source size is 2046x2046.
>> The video blitter is only very little slower than the Xv method.
>> However, it's worst disadvantage is that it cannot scale the video.
>> The video will always be shown in its original size; if the video is
>> larger than the visible screen, it will be cropped. If it smaller, a
>> black border will be drawn. Furthermore, there are no video properties
>> such as contrast, brightness, etc.
> So, when I enable this as the video output, bobdeint starts acting like
> it does when you give "bobdeint" as an argument to the "Custom Filters"
> option in the Setup > Tv Settings > Playback menu; which is splitting
> the screen horizontally in two halves, each displaying one field. Of
> course, this is due to the fact that bobdeint only works on Xv or XvMC
> output. Using this Video blitter method, the output comes from the
> framebuffer, as stated above.
> My experience up till now has been that the combination of SiS + Xv +
> bobdeint gives vertical jitter (now and then) because there is no
> (driver or OpenGL) Vsync support. My question: can the source code of
> either bobdeint or the the non-Xv video output (which one handles this?)
> be modified to have the screen built up correctly, that is with the
> fields interweaved and not split screen?
> -- Jeroen
> mythtv-dev mailing list
> mythtv-dev at mythtv.org
I struggled with an asus pundit to. tried tv-out, wasn't happy with
picture quality, after that i build a vga to rgb converter, wasn't happy
with that either. I spent several days trying diffrent modelines,
interlace filters etc but the bottom line is that the sis 315 is a peace
Now i'm running a new system with a cheap Geforce MX400, and the picture
quality and framerate when using xv + bob is almost better than my settop
So do i have a point?
By new hardware, you will lose your mind trying different settings on the
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