I am capturing a 1080p/30 FPS stream from my webcam with Xvid over VfW.
I used the settings from this guide: http://www.bandicam.com/faqs/vfw-x264-xvid-divx-h264-codec/
Quality is very good, file size tolerable, but the movie jerks slightly. On fast movement its only barely noticeable, but on slow movements you can clearly see it. As if it seems to forget to display 1 or 2 frames and then suddenly jumps ahead to compensate.
Anyone know how I can get this toned down or removed completely?
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It sounds like your computer isn't fast enough to capture and encode 1080p at 30 fps with x264vfw. If you're already using the ultrafast preset you just have to try a different codec. Like UT Video Codec or HuffYUV. Or capture/encode with a smaller frame size.
To verify it's a capture problem not a playback problem, open the video in an editor and step through frame by frame. Are there skips or duplicate frames? That indicates a capture problem. If there are no skips or duplicates you have a playback problem.
I am not using x264vfw, Im using Xvid.
My PC is fast enough, I have an average of 17% CPU usage while encoding, 25% max.
I already tested if its a playback problem but on 3 different PCs with different players and one standalone media player this jerking is happening too.
HuffYUV doesnt work with the program I use and lossless produces files that are just too big.
x264vfw works fine picture-wise, but causes sound sync problems.
With 30 fps video capture there is a new frame arriving every 1/30 second. If the CPU is busy compressing the previous frame when the new one is available the new one may by skipped. Often the software recognizes that it lost a frame and enters a null frame ("repeat the previous frame") as a placeholder in the encoded video. When that happens you'll see the same frame twice in a row and you'll notice that a frame is missing in the sequence.
What CPU are you running? You might try using Divx instead of Xvid. Divx (the h.264 part 2 encoder, not the h.264 part 4 encoder or the h.265 encoder) at its fastest settings is about twice as fast as Xvid at its fastest settings. You need to purchase Divx to get access to those settings though. The free version doesn't allow them.
Make sure you've checked everything in this post: http://forum.videohelp.com/threads/104098-Why-does-your-system-drop-frames
You capture lossless then go back and perform an encoding with the desired high compression codec to get a small file.
Ill try the rest of your suggestions and report back. Thank you.
Check your webcam settings. Many record VFR or variable rates, which of course when recorded to AVI and CFR can mean duplicate frames and jerky playback. If you can record 30FPS CFR in the webcam, then set it to that
However, I cant change that in the options of my webcam. Is there a way to tell the encoder to go VFR?
During quick motions, usually webcam will output a higher FPS, so motion is ok. The problem occurs when you try to "force" it to AVI and CFR and the VFR=>CFR conversion isn't done ideally when there are transitions in the frame rate
AVI container doesn't support VFR. AFAIK the bandicam interface uses VFW and records to AVI only. xvidvfw.dll only records to AVI as well.
(But you can use VFR with other containers and xvid when encoded without VFW, that doesn't help you here)
x264vfw at the ultrafast preset is more than twice as fast (95 to 100 fps) and can consume a lot more CPU.
Are you compressing audio too? Try uncompressed audio.
Not all web cam do true 1080p/30fps or 60fps you need check with who make it you may want to try 720p/30fps & 60fps and do keep in mind that USB can't handle RAW data of 1080p so the so only web cam out there hardware h264 encoder model.
I just switched cameras. From my Logitech C930e to my old C920, which are supposedly pretty much the same cams, except that the C930e has a higher field of view.
To make the story short, it works perfectly with the C920 on the same MJPEG stream as I used on the C930e. No more desync and no stuttering. No matter if i use Xvid or x264vfw. Thus the C930e really seems to be a VFR cam while C920 is CFR.
So I guess Ill just stick with the C920 and x264vfw and maybe put the lens of the C930e on it.
Thanks for your suggestions guys!
Another factor that MIGHT be causing performance issues in the capture process:
I have a Logitech webcam too, and its drivers include a pesky "Facebook service" or something
After I disabled the uselessware, the damn thing finally started to work correctly.
I checked for something like that. But the C930e doesnt come with software or even extra drivers.
I didnt install any software for the C920 either.
That is not software that is started with the camera, is running in the background, installed automatically or is needed in any way. That settings software is a joke anyway. Every other integrated settings in recording software (like Virtual Dub) can change more on the camera than it can.
The C920 however has its own driver and software that is more or less needed, unless you only want UVC modes.