Category | hvr-1600

Tonight I finally finished the HVR-1600 ALSA cleanup and submitted what I hope is the final PULL request to get it into the mainline. While I was there, I took a quick look at how well tvtime works with the HVR-1600 - in short: it doesn't work, and it fails in a way that I suspect would leave most users scratching their heads (in fact, I was only able to understand why it didn't work by examining the source code). I started to look at the issues in terms of what will be required to support the HVR-1600, and what would be required to make tvtime better report the reason for failure in cases...

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Things are moving along - last night I issued PULL requests for the em28xx PAL VBI support, as well as some cleanups for the HVR-1600 ALSA support that Mauro asked for. http://kernellabs.com/hg/~dheitmueller/em28xx-pal-vbi-2/ http://kernellabs.com/hg/~dheitmueller/hvr-1600-alsa-2/ I also checked in the patches I referred to last week when doing cx88 testing with tvtime (testing with a PCTV 800i). There is still definitely a problem there with the cx88 VBI implementation that needs to be dug into, but I haven't had time to do it yet. http://kernellabs.com/hg/~dheitmueller/tvtime/ I...

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There is now a tree that users are welcome to test which provides an ALSA interface for the HVR-1600: http://kernellabs.com/hg/~dheitmueller/hvr-1600-alsa-2 As was the case with the ClearQAM improvements, we have ONELAN Limited to thank for sponsoring this work. One thing that is interesting: as a result of wanting to do some testing, I noticed that neither tvtime nor mplayer really work gracefully with the HVR-1600. Both applications only support raw video streaming via MMAP, and the cx18 driver only supports the read() interface. Also, neither support the HM12 colorspace that is specific...

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Just a heads up to those who were kind enough to try out my testing tree for the HVR-1600 ClearQAM performance improvements: the fixes were merged into the mainline on Friday. So at some point you should stop using my private tree and switch back to the mainline v4l-dvb tree at: http://linuxtv.org/hg/v4l-dvb My tree will be removed from the KernelLabs HG repository towards the end of the week to prevent people from accidentally using it when they should be using the mainline code.

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I spent some time this weekend dealing with various users of the "DVICO Dual Digital 4" who were seeing that zl10353 regression I have fixed on four other boards so far. I can say some choice words about the person who submitted the patch that caused the breakage, or the person who blindly accepted it upstream without considering the implications for all the other products, but there isn't much value in pointing fingers at this point. I just don't have the time/energy to go through and fix *all* the effected products, so I have to deal with them as people report the problem. The big project...

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While Steven continues to churn away on ALSA audio and VBI support for the HVR-1800, I have started working on a project to do ALSA audio for the HVR-1600. So if you have an interest in being able to use the raw analog video capabilities for the 1600, stay tuned! The call for testers for the ClearQAM fixes has been very successful, and I am happy to report that 100% of the people who have done testing have seen a significant improvement in ClearQAM performance, with none reporting a regression. That said, I will be issuing a PULL request this weekend to get the changes into the mainline v4l-dvb...

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If you are an HVR-1600 user who has noticed the ClearQAM tuning performance under Linux was worse than under Windows, this should make you happy. As a result of the work described in the previous post, there is now a tree that contains the various fixes: http://www.kernellabs.com/hg/~dheitmueller/hvr-1600-perf-2 The goal is to submit this upstream, but before that we want to get some people to try it out first and submit feedback on their experience. Thanks go out to ONELAN Limited for sponsoring this work! Feedback (good or bad) on the blog or the linux-media mailing list would...

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Haven't had much time to update the blog lately. All week I've been quietly grinding away at two basic issues: PAL VBI support for the em28xx chip, and identifying/addressing the HVR-1600 performance problem. I often get questions from users along the lines of "how do you make boards work?". Reverse engineering is a bit of a black art, but I figured I would offer some insight as to how the process works. If you don't actually care how tuners are designed and how we figure out how to make them work, stop reading now. If this stuff interests you, read on, and feel free to put something in the comments...

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