Questions tagged [compression]
The use of identifying patterns in video to reduce the required data rate required to create a video stream.
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Export Frames of 10 BPC Video File with ffmpeg
I have several hundred 1080p 59.94fps 10-bit-per-channel (bpc) AVC-Intra Class 100 MXF encoded video files. I would like to extract the frames of this video file and export them to disk in a 16-bit ...
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How can I change/reduce the bitrate of AVI files using Adobe Premiere Pro CC or other tools?
I'm using Eprime and Experiment Builder which requires files in AVI format (AVI-XVid). The files are quite small already (various 2 second clips under 1mb), but are still too large which crash the ...
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What's the difference between "visually lossless" and real lossless and what does this mean for future encodes?
In FFmpeg's H.264 Video Encoding Guide we are told:
Tip: If you're looking for an output that is roughly "visually lossless" but not technically lossless, use a -crf value of around 17 or 18 (you'...
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Some H.264 videos that I have seem to have excessive bitrate, is there a way to determine/find their recommended bitrate?
So I have some videos that are Full HD, h264 but they have over 30M bitrate at 30 FPS, they are SDR and their quality is not very impressive so it seems excessive and unnatural for such unimpressive ...
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Recompressing 1080p h264 collection to HEVC - Target Bitrate For Minimal Loss
My understanding is that HEVC (aka h265) can provide roughly the same video quality as h264 in roughly half the space, for 1080p+ footage. I have a large collection that I would like to re-encode to ...
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What happens when you use a specific CRF value on a already encoded x264 video?
If there is a h.264 video, and I use -crf 17 I sometimes I get a lower bitrate, but the weird thing is - most of the time get a higher ones.
I am trying to get this setting because I think some ...
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ffmpeg clear video cache
I am running a compression script to compress my large AVI files to small mp4 files. The script look like this
#!/bin/bash
FILEPATH="$1"
COMPRESSIONPATH="$2"
ffmpeg -i $FILEPATH -vcodec h264 -acodec ...
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Before I throw away these massive uncompressed VHS digitizations, what kind of post processing can I do to improve them?
An uncompressed digitized VHS tape is like 60 gigs. Obviously way too big. I can compress it down using H.265 and get basically the same quality. But before I do that, is there any production ...
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ffmpeg video compression : Compress captured video being before saving to file
Is there a way one can compress captured video input before saving to file? I have raspberry pi that I am using to record youtube videos. 1-2 min video takes over a Gb of space. I cant compress the ...
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What happens when a compressed video is played back?
I've been reading up on video compression. I understand that 'raw' media file sizes are to big for practical usage so they have to be compressed, but I'm wondering what happens when the video is being ...
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MJPEG Streaming
in https://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/Video/pktvideoaag.html
it says:
Another type of video compression is MJPEG … the resulting video stream is larger but the packet sizes ...
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mp4 to wmv AND file compression
I have a mp4 from a video created in iMovie 10.
The original output is about 1.5 GB.
I uploaded it to youtube to use their compression and re-downloaded.
I now have an mp4 at 236mb.
I need to ...
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Using ffmpeg to add height (as black bars) to video file without quality loss
I have a file of resolution 3840x1632, but my TV stretches the picture vertically to fill up all 2160 pixels of height. Is it possible to use ffmpeg to add blank / black height, while preserving the ...
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Grime-like blocking compression artifacts on the decompressed video (H.264)
During watching H.264 compressed videos one faced several times with an artifacts.
Example 1:
Example 2:
Wikipedia's article [1] tells that the typical reason is «Data errors in the compressed bit-...
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Why does people seem transparent in this video
People seem transparent in that video. What does explain that?
I posted on the Physics community, believing that it was related to some optical effect. But I've been told that it may be related to ...
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Video cam with poor compression ratio (H.264 produces videos at 2.9MB/sec)
I just purchased a cheap dashboard video-camera that is advertised to have a H.264 codec inside. However, after the first video test I have seen that a 43sec movie takes 123MB! How is this possible. I ...
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Why does motion compensation need a decoder?
I know that motion compensation is the process of using the motion estimaton MV information and then compensating it to describe only the differences between reference frame and the motion estimation ...
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Different rate distortion curves for two videos encoded with same parameters in FFMPEG
I encoded two videos (ParkJoy and Sintel) in FFMPEG by H.264 with same parameters (GOP size, QP, frame rate, resolution etc.) and obtained rate-distortion plots (mean PSNR of Y channel vs bitrate). I ...
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How do I avoid objects having flickering edges when I encode a screen recording to mp4 using x264 and ffmpeg?
The Goal
I'm creating short tutorials by recording my screen (720p30fps). The content is just a recording of using some desktop software - so mouse moving and opening dialogs, typing, drawing shapes, ...
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Lossless and lossy compression techniques
Are MPEG and H.264 Lossless??
I need a brief explanation about lossy and lossles... And which compression technique is generally using in CCTV Surveillance applications of video??
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Optimizing HTML5 video for best quality
I have a 3 minute video I'd like to embed on a web page. The problem is that despite best efforts, the file size of the video ends up being over 30 mb. I would like the size to be near 10 mb. I have ...
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Are JPEG compression and H.264 intraframe compression the same process?
I was looking at how JPEG compression works, and to me it seems to be really similar to what H.264 (and other video codecs) does with its intraframe prediction step.
In both algorithms the image ...
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Does increasing the framerate while not changing the content affects compression quality?
This question has no practical importance for a regular video production pipeline, but nonetheless it's something I find fascinating because it would imply video codecs use temporal sub-sampling ...
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AVI Capture in VirtualDub: MP3 Compression
I would like to capture my old VHS tapes to my HDD. I already was successful installing the xvid codec which gives me an acceptable video compression.
But somehow I am not able to set audio ...
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mp4 file expands wildly when shortening clip
noob here,
I took a video of myself for a wedding greeting with my phone (LG Nexus 5 [Android]) sitting (the phone that is) in a windshield suction holder.
The video is 3'42" long and when downloaded ...
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mov to mp4 conversion produces grainy results
I am using handbrake to compress 250mb of 3d animation stored in .mov. This is how the mov looks:
The compressed version has some artifacts. Like it doesn't have enough shades of grey:
How can I ...
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Reencoding H.264 to H.264 made it 40% larger
I've got some livestreamed footage (encoded with constant bitrate), and I've been trying to reduce the file size for long-term storage. I figured that since encoding speed is no longer a constraint ...
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Best possible quality setting for screen recording (not games) and web presentation
Screen videos have text and simple geometric shapes, which need to
stay sharp, detailed and crispy. The color should also remain
untouched. With screen grabs, I want e.g. IBM blue to show as IBM blue
...
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Please Explain the Codecs in my Example [closed]
Can someone explain what's happening in my project? Please use as much detail as possible, I just want to learn, thanks.
I have an Apache web server. It contains many videos (.mp4 .mkv which are ?...
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Archiving raw video
I am trying to organize the videos on my external harddrive. I have a lot of home video shot with a hand held camera, and now I am using a GoPro 4 camera that I record 4K video with. It consumes a lot ...
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Largest input image size when encoding a video?
I got a bunch of really large 16 bit videos, approaching 65535×65535 pixels in size. These are essentially high quality timelapse panoramas. I want to convert them to a 7680×4320 movie (8K UHD, 8 bit)....
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Chroma subsampling notation - rules
Are there some simple arithmetical relations (rules, properties) between numbers in x:y:z chroma subsampling notation?
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Video compression- how to prioritize one area over another?
I'm not sure if what I'm asking is possible, but here's the situation.
I have a video I have made for distribution on the Internet (YouTube, Vimeo, etc.)
The video clip is a composite of the ...
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How does the h.264 encoder determine where to put i-frames?
I'm reading a bit on I-frames and their counterparts, P-frames and B-frames. I understand the usage. I-frames are the key to the compression and following P and B-frames can use the data in I-frames ...
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What deinterlacing filter should I use to encode/compress a PAL MPEG-2 576i 25fps raw file?
I have a PAL MPEG-2 576i 25fps raw capture (presumably either straight from satellite or a DVD recorder) that I would like to encode to AVC. I'd like to deinterlace the file during compression with ...
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Prediction and Motion Estimation
As far as I understand, the motion estimation is a process, where when we have two frames t and t+1 we search for the blocks/pixels that changed position and then encode that change with a motion ...
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Compressing of DSLR video
I m recording full HD video in 1080p /30p format with my Nikon D5200 but i find the size of video is to high i.e. 10 GB for an hour. Now i want to compress it to lesser size in the range of 1-2 GB ...
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Is there a way to improve quality for videos with snow/confetti/LCD in background?
The effect I'm referring to:
Essentially, the snow/confetti in the shot means lots of motion, hence a lot of the available bitrate is taken up by it, thereby ...
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If I limit the color spectrum of a video, will it compress to a smaller file size?
I know that in exporting images, if I use an indexed color format when I save (such as GIF or PNG with indexed color mode), I can dramatically reduce the file size of the resulting export. My ...
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How do you dramatically reduce the size of a video while keeping the quality as much as possible?
I'm very surprised how the video i have recorded with my camera are so heavy for small length (i have 4GB for only 20min). I've been trying compression softwares like handbrake, but it doesn't reduce ...
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Trading off resolution vs quality
I have some 720p 30FPS H.264 video that I want to downsample for online backup. I want to get to somewhere around 10% to 20% of the existing size, which will evidently require a large sacrifice in ...
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Big difference in the video file size after the conversion (.mov to .mp4)
After converting from .mov into .mp4, a video file is greatly reduced in size (.mov - 75,2mb .mp4 - 11,9mb) - does this mean that the converted video degraded (loss of color information, or the ...
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Converting WMV to MP4
I just joined this community and hope my question is acceptable since it is quite "noob" like.
I have a .wmv video file that is 1280x720 and causes windows media player to abort after excessive ...
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Best way to trim and save an existing mp4
If I have an existing MP4/H264 video file and I need to trim the start and end,
Then save it as an MP4 again,
Are there any recommendations on export settings?
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Convert 1920x1080 Video to 720x480 With Letterboxing
I'm trying to find the best application on windows to do this HD to SD conversion for a video server which requires files to be exactly 720x480/29.97fps MP4 H.264 to function. I can't find any options ...
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Techniques for compressing a slideshow presentation video?
I often do QuickTime screen recordings of slideshow presentations (e.g. Keynote).
These videos are 1080p 60fps and mostly text. They can go for minutes at a time with the same exact frame on-screen (...
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Compressing a large MP4 file that is on 2.30mins long
I have been sent a video that is only 2.30 mins long. But is a whopping 168mb, unfortunetely this has to be embedded into an app - so I need it as small as possible. I need to get the file size down ...
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Recompressing many huge MOV files
My camcorder produces huge MOV files, and I use it for about 1 hour every day, which gives me more than 7 GB of data per day (around 128 MB per minute of recording). Here is the codec information ...
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How to compromise between byte rate, resolution and fps
I want to stream a video on a device full screen (therefore, the dimensions of the display are fixed)
What should I focus on to offer the best experience for a given bandwidth? Should I have other ...
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Which measurements can I take using which programs to exploit the already low quality and save as much space as possible?
This is the best my actioncam can create.
My goal is to take advantage of this low quality and save as much harddrive space as possible so visible quality remains.
Which measurements can I take ...
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