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Re: so sick of vendors who advertise linux compatibility but no real support

I've been trying to find a PC104+ MPEG4 encoder to handle this task and

> thought I found one. I bought an encoder that advertised all of the > functionality I needed: pre-scaling, control over constant bitrate > encoding, ability to control IPB frame sequencing, and multiplexing of > audio data in several different formats. Once I got the unit and started > playing with it I found out how much I was mislead by the vendor.

You should name the vendor, and let him see his sales drop. When he'll wonder why, the situation may change.

--
__Pascal Bourguignon__                     http://www.informatimago.com/

THIS IS A 100% MATTER PRODUCT: In the unlikely event that this
merchandise should contact antimatter in any form, a catastrophic
explosion will result.
Reply to
Pascal Bourguignon
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Perhaps you ought to send this rant to the vendor. It might be more effective that way. It is, after all, his fault that the Linux drivers for his product are substandard.

--
 -| Bob Hauck
 -| Hooray for San Fancisco values!
 -| http://www.haucks.org/
Reply to
Bob Hauck

Thanks for the followups.

I've managed to reverse engineer enough of the driver functions in the video encoder to make use of it but I stick by my original comment. Eurotech/Parvus should not be advertising the product for linux use with the current driver that they make available. It is not documented well enough nor well tested.

The support chips are Phillips SAA so they have publicly available datasheets but the actual MPEG4 encoder is the INTUNE6400 and it has no publicly available API documentation for the firmware. I was only able to reverse engineer the register values by trial and error to get proper keyframe insertion and bitrate values. It also does not do a proper I/O wait while waiting for the next available frame to go into the PCI memory buffer so I end up with a really annoying CPU hog polling the (frame available) status. I also get a sporatic (unstable TSC error) when loading the driver. To fix it I have to remove and reinsert the driver. This is not acceptable or the final product. I'm also seeing too many MPEG4 frames that seem to be non-conforming: macroblock errors show up while decoding in mplayer or ffplay and they show up with the same macroblock numbers within the frame. This leads me to believe an error exists in the MPEG4 encoder firmware..

I will be evaluating the Sensoray 314 product as a possible replacement. I've been in contact with their tech folks, who seem to know a bit more about linux and it sounds like they are willing to look at fixing the shortcomings I've identified in their driver: no support for the poll() or select() syscalls, and the addition of mmap() to map the MPEG frame directly to user-land space. Again, they don't include real documentation for the linux driver either: just an example RTP server program.

The only other comparable product I've seen is marketed in the UK and I've got concerns about USA availability, lead times, and support.

Why does it have to be this hard? Oh yeah, it's because linux is all about "choices" :^P

OK. 4AM...Time to sleep.

Reply to
noone

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