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Video Capture SDK .Net - Main Demo encoding problem

Nov 17 (11 months ago)
WYPoon wrote
I find the SDK is simple to use with many useful functions that meet all my requirements. However, there is a problem in encoding that is the output audio signal is always not in sync with the output video signal. There are about 350-370ms difference with them. Although, I can adjust this difference in FFMpeg (EXE), there are no ways for other encoding method. Is it my setting problem or does it only exist in demo version or anything else?
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14 Answers
Nov 18 (11 months ago)
Roman Minyaylov agent wrote
Nov 24 (11 months ago)
WYPoon wrote
Sorry for the late reply. Here is the logs. Please take a look.
Nov 27 (11 months ago)
Roman Minyaylov agent wrote
Try to switch to direct MP4 output, v10 or v11, instead FFMPEG output.
Nov 27 (11 months ago)
WYPoon wrote
I ve try to use the direct MP4 output. However I found another problem, i.e. no matter I chose 30 or 60 fps input video signal, I get a 39.XX fps output encoded file. Is there any ways to fix the output frame rate to set at our desired values, e.g. 30 or 60 fps?
Nov 27 (11 months ago)
WYPoon wrote
Furthermore, if using FFMPEG output, does the delay time is the same for different resolutions and frame rate inputs?
Nov 28 (11 months ago)
Roman Minyaylov agent wrote
For default MP4 output frame rate is variable...

For FFMPEG output we do not set delay value.
Nov 28 (11 months ago)
WYPoon wrote
For MP4 output, can I have a method to set a fixed output frame rate?

For FFMPEG output, I did not see any delay on preview, however, the encoded file had about 370 ms delay.
Nov 28 (11 months ago)
Roman Minyaylov agent wrote
We working on MP4 constant frame rate now, not ready yet.
Nov 28 (11 months ago)
WYPoon wrote
When will the constant frame rate MP4 be ready? I really need constant frame rate output for my current project. If the frame rate cannot be set and fixed, I must then use the FFMPEG output.

Furthermore, does the delay in FFMPEG output related to any audio or video buffers? I have tried FFMPEG and FFPLAY to capture and preview directshow filter sources, but the preview on FFPLAY is "stuttered". After changing different settings on the buffer values, I finally got a more or less smooth preview but it is not perfect. Then I try your product and much appreciate the result.

I am still try different settings on your product and learning how to use it. Do you have any documents that I can download so that I can have a better understanding about your product.
Nov 29 (11 months ago)
Roman Minyaylov agent wrote
Please switch to v10 encoder like shown on screenshot to get constant frame rate.

For v11 NVENC will be available within several days, for v11 CPU (Microsoft) still on work.
Jan 01 (10 months ago)
WYPoon wrote
Sorry for the late reply, I ve switch to V10 encoder with HW available: INTEL QSV. I selected Input format with frame rate at 60 fps. However the output file shows frame rate at 39 fps. Even though, I set the frame rate at 30 fps, the output frame rate showed also at 30 fps.

I ve tested with different input resolutions:
1920 X 1080, output frame rate is 39 fps (input frame rate 30 or 60 fps)
1280 X 720, output frame rate is 60 fps (input frame rate 30 or 60 fps)
720 X 480, output frame rate is 60 fps (input frame rate 30 or 60 fps)

Are there any settings so that I can get the output frame rate to be the same as the input frame rate?

SDK Version 10.5.35.0

Jan 01 (10 months ago)
WYPoon wrote
Sorry for the typing mistakes.

I ve switch to V10 encoder with HW available: INTEL QSV. I selected Input format with frame rate at 60 fps. However the output file shows frame rate at 39 fps. Even though, I set the frame rate at 30 fps, the output frame rate showed also at 39 fps.

I ve tested with different input resolutions:
1920 X 1080, output frame rate is 39 fps (input frame rate 30 or 60 fps)
1280 X 720, output frame rate is 60 fps (input frame rate 30 or 60 fps)
720 X 480, output frame rate is 60 fps (input frame rate 30 or 60 fps)

Are there any settings so that I can get the output frame rate to be the same as the input frame rate?

SDK Version 10.5.35.0
Jan 02 (10 months ago)
WYPoon wrote
Today I have tried 1080i 60 fps input source with a low end PC. The output frame rate is far below 60 fps with about 15-20 fps using V8, V10 and V11 encoder. Is it normal? Can I get an encoded video with the output frame rate same as input frame rate? For FFMPEG encoding, I can set the output frame rate as I request. This is very important to my application. Please give me some advice.
Jan 23 (9 months ago)
Roman Minyaylov agent wrote
Please upgrade to latest SDK version released today. Try to check V11 encoder with FFMPEG muxer enabled, that should made constant frame rate.