Hans, I reinstalled the old system. It was Ubuntu Feisty with the ivtv driver version 0.10.0
Here the dmesg snippet: [ 19.404000] ivtv: ==================== START INIT IVTV ==================== [ 19.404000] ivtv: version 0.10.1 (tagged release) loading [ 19.404000] ivtv: Linux version: 2.6.20-15-generic SMP mod_unload 586 [ 19.404000] ivtv: In case of problems please include the debug info between [ 19.404000] ivtv: the START INIT IVTV and END INIT IVTV lines, along with [ 19.404000] ivtv: any module options, when mailing the ivtv-users mailinglist. [ 19.404000] ivtv0: Autodetected Yuan MPC622 card (cx23416 based) [ 19.404000] ivtv0: Unreasonably low latency timer, setting to 64 (was 32) [ 20.876000] ivtv0: loaded v4l-cx2341x-enc.fw firmware (262144 bytes) [ 21.104000] ivtv0: Encoder revision: 0x02050032 [ 21.104000] ivtv0: Recommended firmware version is 0x02060039. [ 21.188000] cx25840 0-0044: cx25843-23 found @ 0x88 (ivtv i2c driver #0) [ 26.188000] ivtv0: Registered device video0 for encoder MPEG (4 MB) [ 26.188000] ivtv0: Registered device video32 for encoder YUV (2 MB) [ 26.188000] ivtv0: Registered device vbi0 for encoder VBI (1 MB) [ 26.188000] ivtv0: Registered device video24 for encoder PCM audio (1 MB) [ 26.568000] ivtv0: Initialized Yuan MPC622, card #0 [ 26.568000] ivtv: ==================== END INIT IVTV ==================== You may believe it or not this driver produces a correct stream without any B-Frames. To prove my words here are two links to captured streams. One with 2 B-Frames one with 0 B-Frames. http://www.bms-austria.com/~pipelka/2bframes.mpeg http://www.bms-austria.com/~pipelka/0bframes.mpeg Open them with e.g. avidemux and check the frame types. The following commands where used to create the streams: v4l2-ctl -i 1 v4l2-ctl -s pal v4l2-ctl -c video_b_frames=2 cat /dev/video0 > 2bframes.mpeg v4l2-ctl -c video_b_frames=0 cat /dev/video0 > 0bframes.mpeg Regards, Alex Am Di 18.11.2008 20:57 schrieb Hans Verkuil <[EMAIL PROTECTED]>: > On Tuesday 18 November 2008 18:13:04 Alexander Pipelka wrote: > > Hans, > > > > The older version of the driver supported 0 B-Frames (I'm 100% > > sure). > > > > I need this for very fast frame navigation in a MPEG stream. > > It worked with the driver included in Ubuntu Edgy (I think it was > > version 0.7.4 of the driver). > > > > Unfortunately I updated that machine to Ubuntu Hardy and the problem > > appeared. > > > > Well, I could reinstall an other machine with Ubuntu Edgy to > > *verify* that the 0 B-Frame thing works, but I already know this, > > ... > > > > Please help ! > > I am not convinced. The only difference I've found between 0.7.4 and > the > latest driver when it comes to B-frames was corrected by my patch. As > far as I can tell 0.7.4 used the same firmware as well. > > I vaguely remember that someone tried it with an old ivtv version as > well in the past and got a similar results. However, I can't find the > specifics so I might be wrong. > > The upshot is that I *really* need to see proof that this ever worked > (and worked with the same firmware as well!) before I go and spend a > lot of time figuring out what changed. The fact that you could set > B-frames to 0 using ivtvctl doesn't mean at all that it actually > worked. Actually the value 0 that was passed to the firmware in 0.7.4 > was not according to the fw docs since they specific that you have to > pass '#bframes + 1' to the firmware, so '0' should be an illegal > value. > > Regards, > > Hans > > > > > Alex > > > > Hans Verkuil schrieb: > > On Tuesday 18 November 2008 08:26:16 Levente Novák wrote: > > > > Hi, > > > > Is there any advance on the topic of B-frames problem on PVR-150s > > and > > PVR-250s? A few days ago I tested Hans' patch and while my PVR-150 > > MCE does now save a non-zero length stream if th number of B-frames > > is set to 0, this stream has not 0 but 1 B-frames per P-frames. > > Beside this, even if it seems to work OK with 1 or 2 B-frames, the > > stream is choppy and unusable with 3 or 4. > > > > > > My patch fixes the zero-length stream issue, but that's all. I don't > > believe it ever gave you a stream with 0 B-frames. I suspect that > > the > > firmware forces a minimum of 1 B-frame. > > > > If you can prove that the older driver actually gave you 0 B-frames, > > then I'll take another look. But I believe that the conclusion > > simply > > is that you need a minimum of 1 B-frame. > > > > Regards, > > > > Hans > > > > _______________________________________________ > > ivtv-users mailing list > > [email protected] > > http://ivtvdriver.org/mailman/listinfo/ivtv-users > > _______________________________________________ ivtv-users mailing list [email protected] http://ivtvdriver.org/mailman/listinfo/ivtv-users
