intentional delay, display is choppy...

[hobokengolf]

I wish to create an intentional delay of a webcam display of four seconds using VLC Lan.

I can do this under advanced options, setting the cache to 4000 - however - it plays very choppy basically 2 seconds video, 2 second pause and then again 2 seconds video. I can lower the frame rate (from 30 to 15 fps) and it runs smoothly (no pauses) - but I would like to do the full frame rate.

This is a USB camera. It displays at 640x480. I am running on XP with 2 gigabytes and a Athlon X2.

The best for me would be if there were VLC settings or Windows settings that would fix this for me (I was hoping there was some buffer somewhere that I could set to a large number) - but if not - what hardware enhancements would solve my problem? More memory? Faster CPU? Firewire instead of USB? DV instead of Webcam?

I do not wish to lower the resolution or frame rate. I have no need to save the file. I do not need it to be exactly 4 seconds, but close to it.

Thanks in advance,

Hobokengolf

[VLC_help]

Have you checked the memory usage of VLC when do four second caching?
Four seconds of uncompressed RGB video takes about 110 megabytes of memory (4*30*640*480*3). One option to cause delay is to loop the video via other VLC instances.

[hobokengolf]

I did not check the memory usage. I did not realize there was a way to control the memory usage (or is it fixed per instance of VLC)?

The machine I am running this on runs Windows XP Professional and has 2 gigabytes of ram installed. I do not need to run any other software while I am using VLC Lan to set up an intentional webcam delay.

Where do I check VLC Lan's memory usage? How do I increase this? What is the settings for setting up a second instance?

Thanks (sorry, I'm new to this).

HG

[hobokengolf]

the memory usage hovers between 78 megabytes and 115 megabytes according to the windows task manager. I have 1500 megabytes of free memory and my CPU usage varies between 4 and 12% while I am running.

It seems like its not my CPU or memory - but how do I make VLC use more memory?

Thanks again!

[VLC_help]

I meant VLC memory usage via Windows Task Manager. What error messages VLC prints to log (Tools -> Messages... and set Verbosity to 2)?

[hobokengolf]

here's a snip of the error log:

main warning: decoder/packetizer fifo full (data not consumed quickly enough), resetting fifo!
main warning: decoder/packetizer fifo full (data not consumed quickly enough), resetting fifo!
main warning: resampling stopped after 8207000 usec (drift: -10503)
main warning: decoder/packetizer fifo full (data not consumed quickly enough), resetting fifo!
main warning: decoder/packetizer fifo full (data not consumed quickly enough), resetting fifo!
main warning: decoder/packetizer fifo full (data not consumed quickly enough), resetting fifo!
main warning: decoder/packetizer fifo full (data not consumed quickly enough), resetting fifo!
main warning: decoder/packetizer fifo full (data not consumed quickly enough), resetting fifo!
main warning: decoder/packetizer fifo full (data not consumed quickly enough), resetting fifo!
main warning: decoder/packetizer fifo full (data not consumed quickly enough), resetting fifo!
main warning: decoder/packetizer fifo full (data not consumed quickly enough), resetting fifo!
main warning: decoder/packetizer fifo full (data not consumed quickly enough), resetting fifo!
main warning: decoder/packetizer fifo full (data not consumed quickly enough), resetting fifo!
main warning: buffer is 40410 late, triggering upsampling
main warning: decoder/packetizer fifo full (data not consumed quickly enough), resetting fifo!
main warning: decoder/packetizer fifo full (data not consumed quickly enough), resetting fifo!
main warning: resampling stopped after 8207000 usec (drift: -7141)
main warning: decoder/packetizer fifo full (data not consumed quickly enough), resetting fifo!

[VLC_help]

It seems that the video cannot be worked fast enough. What transcoding options you use?

[hobokengolf]

I'm not sure what you mean by 'transcoding' - but I guess that'd have something to do with the video 'codec':

I have theora encoding quality set to 2.

Under x264 I have:
Maximum GOP size: 250
Minimum GOP size: 25
Extra I-Frames Aggressivity: 40
B Frames Between I and P: 0
Influence B Frame Usage: 0
Keep some B Frames as Reference: No
CABAC: Yes
Number of Reference Frames: 1
Skip Loop Filter: No
Loop FilterAlphaC0 and Beta parameters: 0:0
H.264 Leve: 5.1
Interlaced mode: off
Set QP: 26
Quality-Based VBR: 0
Min QP: 10
Max QP: 51
Max QP Step: 4
Average Bitrate Tolerance: 1.00
Max local bitrate: 0
VBV Bufer: 0
Initial VBV Buffer Occupancy: 0.90
QP factor between I and P: 1.4
QP factor between P and B: 1.3
QP difference between chroma and luma: 0
Multipass Ratecontrol: 0
QP curve compression: 0.60
Reduce fluctuations in QP: 20.00
Reduce fluctuations in QP: 0.50
How AQ Distributes Bits: 2
Strength of AQ: 1.00
Partitions to Consider: Normal
Direct MV prediction mode; spatial
Direct Prediction Size: -1
Weighted prediction for B frames: No
Integer pixel motion estimation method: hex
Maximum Motion Vector Search Range: 16
Maximum Motion Vector Length: -1
Minimum Buffer Space Between Threads: -1
Subpixel Motion estimation and partition decision quality: 5
Decide references on a per partition basis: NO
Chroma in Motion Estimation: Yes
Adaptive Spatial Transform Size: No
Trellis RD Quantization: 0
Early Skip Detection on P Frames: Yes
Coefficient Thresholding on P-Frames: Yes
Noise Reduction: 0
Inter Luma Qunatization Deadzone: 21
Intra Luma Quantization Deadzone: 11
Non-deterministic optimizations when threaded: No
Cpu Optimizations: Yes
PSNR computation: No
SSIM Computation: NO
Quiet Mode: No
SPS and PPS id numbers: 0
Access Unit Delimiters: No
Stistics: No
Filename for 2 pass stats file: x264_2pass.log

THANKS!

[VLC_help]

I was just wondering if you do the streaming and disable local playback would it work OK.

[hobokengolf]

I guess you are asking me to isolate the streaming from the playback to see which side is choppy? I'm not very good with VLC LAN (yet) - but I will try to do this.

I will try streaming and saving to file and then replaying the stream (to see if that works okay).