capture identical as hauppauge, startech preview window

[tj1080i]

i read from hauppauge discussions that hd pvr 1 & 2 has the decompressed preview window by the graphics card. i assume startech usb 3.0 is also. i tried vdub decompressor & it doesnt seem not even half the same the way the graphics card displays the decompressed output. i wont post any examples. can this be done without using fraps?

[Brad]

Huh? The StarTech USB3HDCAP is natively uncompressed, so the preview doesn't require decompression in the way that Hauppauge's hardware compression devices do.

[tj1080i]

is it still somewhat decompressed? why does the startech preview appear more crisp/sharp than the captured mp4 that has more artifacts (less sharp). that seems similar to the hd pvrs except the pvrs preview are lower quality, which still appear good in my opinion compared to the captured mp4.

[Brad]

is it still somewhat decompressed?

That's like describing something as "somewhat perfect" or "somewhat dead".

why does the startech preview appear more crisp/sharp than the captured mp4 that has more artifacts (less sharp).

The StarTech uses software compression. The preview is uncompressed. Your captured MP4 is a lossy-compressed version of this uncompressed data. If you care to, you can capture with a lossless compressor, if you have a fast enough and big enough hard drive. The video quality will then be identical to the preview.

the pvrs preview are lower quality, which still appear good in my opinion compared to the captured mp4.

Raise the bitrate, capture with a more efficient H.264 compressor like x264vfw instead of StarTech's own software, or capture lossless and compress to H.264 as a final stage in slower-than-realtime for better quality at the same bitrate.

[tj1080i]

thanks for your helpful info