HDV stream tearing and “pixelating"

[Rob Son]

I connected the Sony Z1U to my PC and transfered the HDV stream. When played back the results are fine for roughly 15 seconds, and then unfailingly, the image starts tearing and “pixelating” never to recover. It seems that the system is handling the “capture” process well – as an illustration, there’s little delay (if any) when the Cineform algorithms process/converts the MPEG2 stream.

My setup includes:

- Dell 360 workstation grade PC. P4 2.8G with 2GB memory
- Adobe’s Premier Pro 1.5.1 with a trial version of Cineform 3.5
- Matrox Pahrellia video card with 128mb ram
- SATA/7200rpm HDD – 400GB. At 40% capacity and reasonably defragged (windows utility claims no additional defrag required)

Anyone saw this one before? Thanks in advance for any help.


Rob Son

[harlequin]

1. I may be way off base , BUT , HD takes some heavy processor capability to playback in realtime.

2. Is it a single hard drive machine ?

if it is that really won't help any either.

[Rob Son]

1. I may be way off base , BUT , HD takes some heavy processor capability to playback in realtime.

2. Is it a single hard drive machine ?

if it is that really won't help any either.

Thanks harlequin
It is a single processor and there are two HDDs - 120Gig for the OS and the other i'm using for video files (the spec of which I mentioned above).

According to most sources, this configuration is reasonable. The problem does not seem to be the playback process within Premier but the source 'captured' file. To verify, I opened the files outside of Premier in Windows Media Player and the symptoms are the same.

[RayL]

Rob

You are not alone. In the (limited) experiments that I've conducted capturing HDV (using Prem Pro 1.5.1 from a Z1) I get the same effect. When I get some time from all my outstanding SD editing (oh, that happy but far-off day!), I plan to track this down. Like curing dropped frames in the old days of DV capturing I expect that better hardware will be needed.

Ray Liffen

[Rob Son]

...You are not alone

Thanks Ray. I'll try and connect with Cineform - they may have some insight into this phenomenon. It would have been nice to have a 'drop frame' indication as is the case with standard DV - simply as a way to gauge the system's capture performance - alas, MPEG2 makes 'separating' individuals frames a bit difficult. I must say though, at 25mb compressed stream on the tape, the 'transfer' process should proceed as if this stream was standard DV - conversion or decompression (in this case to Cineform's own proprietary codec) is supposed to happen immediately after the 'transfer' from the z1 to the PC or in parallel, if the CPU is powerful enough - as was indicated in FAQs I read, including PP's own 1.5.1 update 'readme' file.



If I hear anything - i'll update this forum.



Rob Son

[Richard Payne]

Have you tried HDV capture in Premiere 1.5.1 it also uses the CineForm Codec?
Also have you tried capturing the transport stream and converting afterwards.

I have not seen this problem with CineForm but not used anything less than a 3GHZP4