习近平“4·19讲话”蕴含国家网络治理的“五观”
Tagged with video-quality ffmpeg
54 questions
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Transplanting missing image from 4:3 to cropped 16:9?
Say that I have a widescreen version (16:9) of a certain film that is of higher bitrate than the open-matte fullscreen (4:3). How could I take the areas from the 4:3 that are cropped from the 16:9 and ...
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How is PSNR calculated when the reference file is RGB and the encoded file is YUV?
If I use this command to get PSNR statistics for a file:
ffmpeg -i encoded.mp4 -i reference.nut -lavfi "[0:v]setpts=N[out0];[1:v]setpts=N[out1];[out0][out1]psnr=stats_file=psnr_logfile.txt" -...
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AV1 Encoding Parameters Help - Reduce Variation in Quality from frame to frame
I'm encoding 16 bpc PNG sequences into various lossy video formats for archival purposes because the file sizes are so big. I'm only considering codecs which support 444 and at least 10 bit color. ...
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Advice choosing an archival format; prioritize pixel format or PSNR?
I produce 3D animations and I keep an archive of the final rendered animation (lossless 16 bpc RGB tif sequences) in case I need to re-upload it somewhere else in the future. It is much faster to just ...
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2k
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ffmpeg Config to Produce H.264 Constrained Baseline Profile
It all begins with Plex and appears to end at ffmpeg as the easiest possible solution. I love ffmpeg! I use Plex running on Linux to stream over home network to a Roku. I've used this for years ...
2
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1
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How to encode scenes with different CRF into a H.264 MP4 video with a variable frame rate?
Source Material
Having many scenes which essentially are still frames (for many seconds)
Commonly found in: Slideshows, Screen Recording or Software Mockup/Prototype
? This kind of source material ...
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456
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ffmpeg: video size/quality changes when applying ffmpeg with no filters or other parameters
I've used ffmpeg for years for minor tweaks to sound & video but I know pretty much zero about containers and codecs and whatnot.
I've recently had a need to reduce the physical (disk) size of ...
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In FFMPEG's H.265 encoder, which CRF value leads to "visually lossless" results?
I am trying to shrink some videos from 1920x1080 to 1280x720 and to achieve a reasonable compromise between video quality and file size. I have decided to give FFMPEG's H.265 encoder a try, and now ...
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What actually distinguishes various MPEG-4 Part 2 video codecs (divx, xvid, mpeg4, msmpeg4v1, mp4v, etc.)
I recently audited a large folder containing a variety of encoded videos from 2002-2014. Using ffmpeg, I extracted and recorded metadata, including the video codec used on the film. An example command ...
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Export a video to 4k or 2k with FFMPEG and without lag (UPSCALE VIDEO)
how do I upscale a video to 4k or 2k with ffmpeg? youtube encodes the videos which results in some quality loss of the video. So to make youtube use VP09 encoder on my videos, I have to export the ...
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Why does this script reduce the bitrate of both the video and the audio stream?
I wrote the following script that is meant to remove the unnecessary audio streams, aka dubbing, as well as subtitles from
the movies in my collection:
#!/usr/bin/bash
echo "What is the path to ...
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456
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FFmpeg 5.0 vs 3.4 performance
I was trying to compare ffmpeg 5.0 vs version 3.4.6 in how much performance improvements I would get while transcoding a simple 720p video into a H264 video. On my laptop, I noticed around 5-10% ...
- 353
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Idea validation - CRF's as a service
I was looking for validation for my startup idea. Please flag if this is off-topic.
Idea: CRF's as a service - When encoding h.264 and libvpx videos, I tend to guess good Constant Rate Factors(CRF's) ...
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H264 AVC codec [email protected] vs [email protected]
When I convert a video with ffmpeg, and use mediaInfo to review the metadata, I see the followings for the video codec:
Format : AVC
Format/Info : Advanced Video Codec
Format profile : [email protected] ...
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How do I verify that the H264 video stream is encoded with a single slice per frame?
I'm a software tester and I need to test a certain requirement for a vehicle camera that I'm not sure on how to test.
As in the title it's to verify that each frame is encoded with a single slice. ...
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