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Discussion Starter · #1 ·
I'm trying to capture analog video with the FusionHDTV and convert to a DVD. The software allows this, including a specific DVD setting. However, while the MPEG-2 compression isn't too bad, the resulting video is apparently stretched with replication. The MPEG-2 setting only goes up to 640x480, so I assume this is the maximum resolution of the capture circuitry, and the DVD setting just replicates to get 720x480.


1. Is there any way around this (i.e. to get interpolated scaling or 720 out of the card)?


The audio plays back too fast (on the MyHD). I appears the audio is captured at 44.1 kHz, which is not correct for DVD (supposed to be 48 kHz). I suspect this is an issue with my sound card, but I don't see a way to set it.


2. Is there a way to set/check 48 kHz capture?


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Discussion Starter · #3 ·
Quote:
Originally posted by e vey
It has been a while since I read the White Papers from Brooktree (the folks that invented the TV tuner business and the BT-XXX chips), but I seem to recall that 640x480 is the maximum for the NTSC chips, while PAL can go a bit wider, but not 720.
The horizontal resolution depends on the sample rate.


The ITU-R 601 (formerly CCIR-601) standard ( http://viswiz.gmd.de/DVP/Public/deli...sc/itu_601.htm ), used for almost all professional, standard definition, digital video, specifies 13.5 MHz, which gives 864/858 samples per line (PAL/NTSC), of which 720 are active ( http://www.semiconductors.philips.co...7111AH_V4.html ) However, this resolution does not result in square pixels (PAL pixels are short and fat; NTSC pixels are tall and skinny), as on your computer CRT (which are all square except 1280x1024).


By using a sample rate of 12.27 MHz for NTSC or 14.75 MHz for PAL ( http://www.semiconductors.philips.co...91B_CNV_2.html ) square pixels can be obtained. For NTSC, that would be 640x480, and 768x576 for PAL.


But any sampling rate can be used. I worked with a device that used a 19.6 MHz sample rate, so it had a resolution of 1024 x 480 pixels. (This might be overkill for a bandwidth-limited over-the-air broadcast, but it can be useful for internal video processing prior to broadcast.)


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Strictly speaking, I don't care whether the capture resolution is 640 or 720 for my purposes, but I would prefer not to encode all the way to MPEG-2 at 640 and then re-encode to 720 for DVD.
Quote:
I use ShowShifter for all my recording needs. For archiving, I use Pic Video's MJPEG codec (comes with ShowShifter) which offers light compression/highest quality and is easily edited. Once that is done, another program can be used to compress to MPEG or WMV9 if desired.


For day-to-day recordings, I use Divx or WMV7.


ShowShifter added 48 kHz last year.
1. Will this work with the FusionHDTV (their web page doesn't include this card)?


2. Their web page mentions that their MJPEG format uses their proprietary SSF format. Can this format be read by MPEG encoders (CCE, TMPG, etc.), or does it have to be converted to AVI with their utility?


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