Questions tagged [encoding]
The process and techniques used when storing moving images, sound, metadata and other streams as a digital file.
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Suitable codec and settings to encode videos that can be scrubbed back and forth for making transcripts
For scientific purpose, I'm encoding videos that are going to be transcripted. Since in the process of transcription the person who does the transcription needs constantly to jump back and forth in ...
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Can you fix videos with "error: more than 5 seconds of late video" without re-encoding with ffmpeg?
I have obtained a video, ffprobe for it shows:
$ ffprobe test-000000.mp4
ffprobe version 4.2.7-0ubuntu0.1 Copyright (c) 2007-2022 the FFmpeg developers
...
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '...
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How output multiple stats file for multiple output?
I'm launching encoding ffmpeg using GPU with 2 outputs: one using H264_NVENC and one using HEVC_ENV.
To enable video stats output I'm putting -vstats before input file. To specify output of video ...
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Why, in FFmpeg with libx265 the timestamp tbn parameter is always 1k even when it seems not logical?
I encode with ffmpeg and noticed that when I encode a y4m video in 29,97 FPS into a h265 video with libx265, the parameter of the two videos are the following :
original y4m :
29.97 fps, tbc : 29.97 ...
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Encoding to the same H.264 size as YouTube
I am unable to re-encode an H.264 video that I downloaded from Youtube back to its original size. The MediaInfo is pasted below. The size of the video stream is 20 MB.
I decoded the video into raw YUV ...
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How to re-encode leaving only every Nth frame in?
I have several hours of CCTV footage that I'd like to reasonably quickly skim. If there was a way to take every say 60th frame from it and put together a video from those frames that would be perfect.
...
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How to know which ffmpeg encoders are hardware accelerated?
On any given build of ffmpeg, ffmpeg -encoders will list which encoders can be used for encoding video.
Of the encoders listed, how can I tell which ones use hardware acceleration?
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Understanding YouTube Video Color
When I upload a video to YouTube, the white areas become grey and the colors seem a bit washed out.
This is how it looks locally:
And this is how it looks on YouTube (Screenshot from Firefox):
This ...
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Recording dozens of videostreams simultaneously - software & hardware stack advice required
I have a task to record multiple web-based (HLS) streams simultaneously; we're talking about ~20 streams with possible scaling to ~50 in the future. Each stream comes as an individual link, 1080p, no ...
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ffmpeg demuxer file size
I have used ffmpeg to concatenate two MKV containers with both files having AV1 codec like so:
ffmpeg -f concat -i input.txt -c copy "out.mkv"
Interestingly enough, the first file has ...
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How to mux JPEG into TIFF?
I understand that I can decode and then re-encode JPEG to TIFF using:
ffmpeg -i input.jpeg -pix_fmt rgba output.tiff
But instead I want to do lossless muxing from JPEG into a TIFF container/format. ...
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Different decode performance in two similar H.264 videos
I have two, at first glance very similar mp4 files (A & B), each of them created by different capture software.
File
Captured using
codec
resolution
fps
bitrate
A.mp4
Elgato 4K Capture Utility
h....
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RTMP VS NDI-HX with now WIFI6
I'm trying to make a decision which all boils down to this. When it comes to streaming wirelessly (over WIFI) in a local network to a streaming PC/server, is it better to use NDI-HX or RTMP. Most ...
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What causes, and how to avoid artifacts on uncompressed video?
Wondering what in particular could be causing visual artifacts on uncompressed video and how to avoid it. I am assuming it is due to the encoding, but would need confirmation as I'm not an expert on ...
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Issues in trimming a video with FFmpeg
I have a .webm video captured through a web browser. Using ffmpeg, I want to trim it into its first 30s without re-encoding and quality degradation. But I have issues doing it and ffmpeg complains ...
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FFmpeg saturates memory + CPU usage drops to 0% during very basic conversion of PNG files to MP4 video
I have this Python function that runs ffmpeg with minimal options from the Windows command line:
def run_ffmpeg(frames_path, ffmpeg_path=notebook_directory):
'''
This function runs ffmpeg.exe ...
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Why do identical video conversions produce different bit rate results?
Using Hadbrake I converted the same input video twice with the exact same H.264 settings.
As expected they are mostly identical, but why do they differ in bit rate?
From a logical perspective the ...
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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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Sony PXW-Z280V AVC strange Long GOP pattern
I have video shot using a Sony PXW-Z280V using AVC_3840_2160_HP@L51 with 29.97 frame rate. Upon analyzing the MXF file structure, I notice that the Index Entry Array seems incorrect. In particular the ...
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Audio out of sync, can't fixed even converted to CFR
I have a video recorded from Oculus Quest 2. Mostly I recorded videos have audio out of sync, so I always had to convert it to a constant frame rate. It works so far, but the video recorded yesterday ...
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FFMPEG - AMD GPU Transcoding MJPEG to HEVC provides a skewed split screen video
Trying to use AMD GPU for transcoding MJPEG to HEVC using VA-API.
Using this command:
ffmpeg -hwaccel vaapi -hwaccel_device /dev/dri/renderD128 -hwaccel_output_format vaapi -c:v mjpeg -f v4l2 -...
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h264/hevc: non-integer frame rates
I'm having a hard time understanding how non-integer frame rates are implemented in h264 and hevc. For example, I just stepped through a 23.976fps video frame by frame using Shotcut, and looking at ...
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Decode frames from mp4 file while new ones are encoded into a it
I wrote a video player (written in C++ and C#) that shows a live video stream and also encodes it into mp4 file at the same time. I want to also be able to playback (seek backward or forward) the ...
- 101
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FFmpeg optimizations for trimming large video with precision?
I'm playing around with FFmpeg options for large and small videos of different container formats. I'm wanting to trim the video in a performant way that is also accurate.
I've read a lot on this topic ...
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Suitable alternative to Quicktime RLE for alpha-containing non-cartoon videos?
I'm producing a product that involves a composition of several videos, over alpha layers, and there are surprisingly few options aside from image lists. Quicktime's RLE (Run-Length Encoding) codec ...
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How to burn a Blu-ray disk without Encore? (Preferably without spending a lot of money on new software)
I was recommended to post this question here by someone in the Graphical Design exchange, I hope it's within the scope of the exchange but if not please let me know.
I've been working on some wedding ...
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Parallel throughput of Intel QuickSync (QSV) for real time streams
I'm using Intel QuickSync to lower CPU loading of real time video transcode with FFmpeg.
Specifically, qsv is used to deinterlace and decode the input video. A special HW module is used for the ...
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How can I build a MOV (QT-rle) file with minimal unnecessary features?
I understand that my title requires further specification, so allow me to elaborate.
I recently finished a model in Blender and rendered 1000 frames to PNG with alpha. The total size was roughly 2 GB ...
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Interesting features to use in FFmpeg
What are some interesting features or filters of FFmpeg that can lead to fun use-cases or used for improved quality?
For instance, motion interpolation feature to increase FPS for better quality was a ...
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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% ...
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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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How to move all video files with mp3 audio?
My folder has some video files with mp3 audio and some video files with aac audio. I want to move all files which have mp3 audio to another folder. When I asked my friend, he gave me this script:
...
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FFMPEG: Why can't I work in frames instead of HH:MM:SS?
I have a video-only stream that I removed the audio from without re-encoding. The video information is as follows.
hevc (Main 10), yuv420p10le(tv, bt2020nc/bt2020/smpte2084), 3840x1608
Frame ...
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Possible reasons of choppy video
I have a very specific goal: there is a device which is advertised to be able to playback my own media files from USB-pendrive, and I'm intended to do so.
Further details are not disclosed about ...
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What is the anatomy of a video file? [closed]
I am creating a software related to video editing.
So, I need to understand what is a video file, how is it created and how does it work?
One thing that I want to achieve is: I want to be able to add ...
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1
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804
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Encode still image video effectively in FFMPEG
FFMPEG can make video from MP3 file and still image:
ffmpeg.exe -loop 1 -i "img.png" -i "%1" -c:v libx264 -tune stillimage -shortest "%1.mp4"
But it honestly encodes the ...
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HEVC vs H264 video file size
I am doing some experiments on the file size of recorded videos in HEVC vs the ones recorded in H264 using a simple Android app that I developed. My impression was that videos recorded in HEVC should ...
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Pillarboxing AVC/h.264 video with minimal re-encoding?
I have 1440x1080 AVC/h.264 video that should be displayed with a 4:3 aspect ratio (which would correspond to square pixels). I'd like to burn it to a Blu-ray disc to be playable in Blu-ray players, ...
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How is this .mp4 file 596523 hours long?
I came across this joke mp4 file online. (Warning: direct download link to an 8 mb file.) Media players as well as ffmpeg both list the file as having a length of 596523:14:07.00 (!). My first guess ...
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FFmpeg Optimized File Size Video Loop
I am attempting to create a video loop by merging a 15 second video with about 4 minutes of audio. After finding a similar question, I found a command that loops the input video for the length of the ...
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Combining multiple commands to render out different formats, while also resyncing the original file, and not have to render that one out first
After recording a live show, there are several tasks I need to do before I can render out the video file to different formats. I need to trim the file, and then resync the audio as well. After this I ...
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ffmpeg libx264 core 157 vs core 164
For a while I have been using a build of ffmpeg from 2019:
ffmpeg version N-94150-g231d0c819f Copyright (c) 2000-2019 the FFmpeg developers
built with gcc 9.1.1 (GCC) 20190621
configuration: --enable-...
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What x264 encoder is better for upscaling pixel art? Is it x264 8bit or 10bit?
I mostly use Virtualdub2 to upscale my videos (although I am looking for other methods) via two resize filters, Nearest Neighbor and Lanzcos3. Recently I am looking at the x264 encoder to encode my ...
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How do you batch resizes of Genesis videos in FFMPEG?
I am trying to a create 4:3 video upscale encodes with Sega Genesis videos that are usually around 320 x 224 using FFMPEG. While I had been advised to use FFMPEG (and AVISynth) in the past, it was ...
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ffmpeg to convert .avi to .mp4 results in error: Could not find tag for codec dvvideo in stream #0, codec not currently supported in container
I'm trying to convert .avi files to .mp4 using ffmpeg, as lossless-ly as possible.
I tried this command:
ffmpeg -i filename.avi -c:v copy -c:a copy -y filename.mp4
and received this output:
...
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Problem combining multiple filters with ffmpeg
I'm trying to generate a video file out of 3 files:
file #1 and #2 are both dynamically generated image list file;
file #3 is a dynamically generated pcm file;
I need to slow down or speed up the ...
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Are video encoders specialized for certain resolutions?
I have wondered if the encoders used by tools like ffpmeg and hardware encoders like NVENC are more efficient for common resolutions like 1920x1080. I've done a few informal tests with a variety of ...
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FFMPEG 9600x1080 5 video
FFMPEG 9600x1080 5 video stitching outputs black video
Hello everyone. I’m trying to merge 5 1920x1080 videos into a one big 9600x1080 clip. I’m using FFMPEG for it with the following script:
ffmpeg -...
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111
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Where/what to check in Openshot to see why GPU render doesn't work?
I've been using OpenShot for a while on Fedora Linux from 27-33 and mostly not much problems. I did notice occasionally that Render via GPU didn't work, but then I restarted the App, and was ...
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2
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108
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Why is my video file so large when there isn't any video?
Background
I am using Final Cut Pro X on a new M1 MacBook Pro (16gb of RAM) on AC power, and I have noticed that when I export the video project (share) the resulting video file is so much larger than ...
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