6 juillet

Newest 'ffmpeg' Questions - Stack Overflow http://stackoverflow.com/questions/tagged/ffmpeg

• 16:21
  Is there a way to force FFMPEG to decode a video stream with alpha from ​a WebM video encoded with libvpx-vp9? - David Newest 'ffmpeg' Questions - Stack Overflow
  I have a ​WebM file with one video stream that was encoded with VP9 (libvpx-vp9). I wrote a C++ program to extract the frames from the video stream and save them out as PNG's. This works fine except that the resulting PNG's are missing alpha. If I extract the frames from the same WebM file using FFMPEG the resulting PNG's do contain alpha. Here is the output from FFMPEG: $ ffmpeg -c:v libvpx-vp9 -i temp/anim.webm temp/output-%3d.png [libvpx-vp9 ⓐ 0000024732b106c0] v1.10.0-rc1-11-gcb0d8ce31 Last message repeated 1 times Input #0, (...)
• 13:01
  What codec in OpenCV can do a stronger compression than default 'mp4v'? - ullix Newest 'ffmpeg' Questions - Stack Overflow
  My project does video recording from a microscope camera, and one experiment can run for days and even weeks. This takes plenty of filespace, so I want as strong a compression as possible. Quality is not a major concern. Currently I use the default 'mp4v' codec with opencv on Python. It works. I tried all codecs Google could find, and surprisingly, only very few worked. And those few that did work were even worse in compression. Where is the limitation? Is it Opencv (4.11.0.86)? Is it FFMPEG (7.1.1)? Is it the distribution (Ubuntu Mate 25.04)? Is it the CPU (AMD (...)

5 juillet

Newest 'ffmpeg' Questions - Stack Overflow http://stackoverflow.com/questions/tagged/ffmpeg

• 22:14
  Randomly extract video frames from multiple files [closed] - PatraoPedro Newest 'ffmpeg' Questions - Stack Overflow
  I have a folder with hundreds of video files (*.avi), each one with more or less an hour long. What I would like to achieve is a piece of code that could go through each one of those videos and randomly select two or three frames from each file and then stitch it back together or alternatively save the frames in a folder as jpegs. Initially I thought I could do this using R but quickly I've realised that I would need something else possibly working together with R. Is it possible to call FFMPEG from R to do the task (...)
• 18:49
  Moviepy write_videofile works the second time but not the first? - Andrew Best Newest 'ffmpeg' Questions - Stack Overflow
  I'm concatenating a list of video objects together then writing them with write_videofile, weirdly enough the first time I write the file, it plays fine for the first halfish then the first few frames of each clip in the file afterwards plays before freezing. But here's the odd part, If I write the exact same video object right after the first video writes, it writes just fine and plays perfectly. Here's my code from moviepy.editor import VideoFileClip, concatenate_videoclips clipslist = [] clips = (...)
• 14:00
  FFmpeg adds its own metadata - encoder: Lavf58.20.100 - NarūnasK Newest 'ffmpeg' Questions - Stack Overflow
  I've tried to apply the following advice on the flac files: for x in *.flac; do ffmpeg -i "$x" -map 0:a -codec:a copy -map_metadata -1 clean_"$x"; done But it seems, that ffmpeg though removes most metadata, it also adds its own fingerprint. Why does it add this tag? What is the best way to get rid of it? --
• 13:58
  How to remove ffmpeg metadata "software lavf55.7.100" - Joeedomi Newest 'ffmpeg' Questions - Stack Overflow
  I'm using ffmpeg to extract audio from video files, then process the audio and cut it into smaller clip. But when i use ffmpeg to do the extraction, it adds a metadata "software lavf55.7.100" into my audio file, which screws my indexing of cutting. How can i get rid of this? In attached picture, in the middle "Metadata: ISFT : Lavf55.7.100" The string that i'm using is: ffmpeg -i steve.mp4 -map_metadata -1 steve14.wav  (...)
• 05:28
  ffmpeg try to open output file but fail [closed] - Lyhourt Te Newest 'ffmpeg' Questions - Stack Overflow
  In my Windows 11, I use this code to use ffmpeg to convert video from one type to another type. The code is simple, it just loops and finds the target file extension and runs ffmpeg to convert the video This code used to work just fine, but now it's not working anymore. I think it maybe because of the Windows 11 security update. import os import subprocess def convert_ts_to_mp4(folder_path): # Ensure the folder exists if not os.path.isdir(folder_path): print(f"Folder 'folder_path' does not exist.") return # Loop through (...)

4 juillet

Newest 'ffmpeg' Questions - Stack Overflow http://stackoverflow.com/questions/tagged/ffmpeg

• 06:01
  ffmpeg cutting around keyframes is not accurate - swwind Newest 'ffmpeg' Questions - Stack Overflow
  TL;DR: I have a large video that requires transcode to play in browser, rather than using -f hls generate every segments into disk, I want to listen to segment request and generate them on demand. However, cutting using -ss and -to is always not accurate among segments, causing video to glitch at segment borders. Here is the details. First know the video's keyframes timestamps. Like below $ ffprobe -fflags +genpts -v error -skip_frame nokey -show_entries format=duration -show_entries stream=duration -show_entries packet=pts_time,flags -select_streams v -of csv (...)

3 juillet

Newest 'ffmpeg' Questions - Stack Overflow http://stackoverflow.com/questions/tagged/ffmpeg

• 21:06
  Video generation and ffmpeg and locally stored images - Rahul Patil Newest 'ffmpeg' Questions - Stack Overflow
  I am facing issue in ffmpeg while running the below code I'm working on a Flask application that generates a video by combining a sequence of images from a folder and a synthesized audio track using Bark (suno/bark-small). The idea is to use FFmpeg to stitch the images into a video, apply padding and scaling, and then merge it with the generated audio. I'm triggering the /generate-video endpoint with a simple curl POST request, passing a script that gets converted to audio. While the image and audio processing work as expected, FFmpeg fails during execution, and the server (...)
• 10:39
  Flutter ffmpeg_kit_flutter_new can't build Android app in any version - user31929 Newest 'ffmpeg' Questions - Stack Overflow
  I can't build my project on Android ( on Ios it works and the project itself without ffmpeg_kit_flutter_new builds without problems ) This is the error i obtain: /GeneratedPluginRegistrant.java:51: error: cannot find symbol com.antonkarpenko.ffmpegkit.MainActivity.registerWith(shimPluginRegistry.registrarFor("com.antonkarpenko.ffmpegkit.MainActivity")); ^ symbol: class MainActivity location: package com.antonkarpenko.ffmpegkit This is my flutter doctor : [✓] Flutter (Channel stable, 3.19.4, on macOS 15.4.1 24E263 darwin-x64, locale it-IT)  (...)
• 09:41
  Extract motion vectors from x265 (HEVC) encoded video with ffmpeg/libavcodec? - John Allard Newest 'ffmpeg' Questions - Stack Overflow
  I know that one can extract the motion vectors from an h264 encoded via by first setting the flag av_dict_set(&opts, "flags2", "+export_mvs", 0); then you can query the side-data for the motion vectors by doing this sd = av_frame_get_side_data(frame, AV_FRAME_DATA_MOTION_VECTORS); When I looked online to see if you can do something similar with HEVC encoded videos, I wasn't able to find any information. All I found was this by the definition of "AV_FRAME_DATA_MOTION_VECTORS" Motion vectors exported by some (...)

2 juillet

Newest 'ffmpeg' Questions - Stack Overflow http://stackoverflow.com/questions/tagged/ffmpeg

• 20:24
  How to comp portion of first frame onto rest of video without re-encoding? [closed] - jonathan Newest 'ffmpeg' Questions - Stack Overflow
  I am working for a company recording educational screencasts using Goodnotes. The first frame looks fine, but as I work on the document, the page number pops up on the bottom left. My bosses don't like this, so I've been trying to find a way to fix it on the screencast, since I can't find a way to turn it off in Goodnotes. My current solution is taking a screenshot of the clean frame and using Gimp to crop out all but a small rectangle around where the page number would be, exporting that as a PNG and using ffmpeg to overlay that. The resulting image looks great (...)
• 23:04
  Using FFMPEG to join two MTS files together - Reado Newest 'ffmpeg' Questions - Stack Overflow
  I have two MTS video files, each one 2 minutes long. I need to be able to join the files together and convert the format to MPEG4. I have a suitable command line for converting MTS to MP4 but don't know how to join the files together in the first place. Some articles on the web suggest using the CAT command, like: cat video1.mts video2.mts > whole_video.mts However this doesn't work and according to FFMPEG, "whole_video.mts" is only 2 minutes long, not 4 minutes. Does anyone know how to join the files together? Is FFMPEG the best (...)
• 14:49
  Use FFmpeg to create MPEG-DASH files - angel_30 Newest 'ffmpeg' Questions - Stack Overflow
  I know using ffmpeg, we can create MPEG-DASH ready files, including the segments and the .mpd manifest file. For instance, I'm trying this command which works: ffmpeg -re -i .\\video-h264.mkv -map 0 -map 0 -c:a aac -c:v libx264 -b:v:0 800k -b:v:1 300k -s:v:1 320x170 -profile:v:1 baseline -profile:v:0 main -bf 1 -keyint_min 120 -g 120 -sc_threshold 0 -b_strategy 0 -ar:a:1 22050 -use_timeline 1 -use_template 1 -window_size 5 -adaptation_sets "id=0,streams=v id=1,streams=a" -f dash out.mpd But I don't want to segment the video- so a simpler version where we have (...)

1er juillet

Newest 'ffmpeg' Questions - Stack Overflow http://stackoverflow.com/questions/tagged/ffmpeg

• 22:43
  ffmpeg create blank screen with text video - kalafun Newest 'ffmpeg' Questions - Stack Overflow
  I would like to create a video consisting of some text. The video will only be 0.5 seconds long. The background should just be some colour, I am able to create such video from a photo, but cant find anywhere how this could be done without a photo, just using text to create such video.
• 23:02
  UserWarning: x bytes wanted but 0 bytes read at frame index y (out of a total z frames), at time q sec. Using the last valid frame instead - Wiz Newest 'ffmpeg' Questions - Stack Overflow
  I have a script which subclips a larger video and then stitches needed parts together using concatenate and write video file in moviepy. But the problem is everytime i run the script i get the video but the audio is off sync, usually the audio starts normally, but over time becomes delayed. I suspect it is because i want to concatenate around 220 smaller mp4 videos into one big mp4 video, but every smaller clips receives the error:'UserWarning: In file test.mp4, 1555200 bytes wanted but 0 bytes read at frame index y (out of a total y+1 frames), at time x sec. Using the last (...)

30 juin

Newest 'ffmpeg' Questions - Stack Overflow http://stackoverflow.com/questions/tagged/ffmpeg

• 19:10
  ffmpeg dshow - Getting duplicate/dropped frames, I'm not doing anything [closed] - ENunn Newest 'ffmpeg' Questions - Stack Overflow
  I'm messing around with recording my capture card with ffmpeg. No matter what I do I get duplicate and dropped frames. I'm not even doing anything on my computer. Is there a fix for this at all? Here's my command. ffmpeg -hide_banner -rtbufsize 2G -f dshow -video_size 2560x1440 -framerate 60.0002 -pix_fmt bgr24 -video_pin_name 0 -audio_pin_name 1 -i video="AVerMedia HD Capture GC573 1":audio="AVerMedia HD Capture GC573 1" -async 1 -rtbufsize 1M -f dshow -sample_rate 48000 -i audio="Digital Audio (S/PDIF) (Sound Blaster X-Fi Xtreme Audio)" (...) --
• 18:03
  C++/FFmpeg VLC doesn't play 5.1 audio output - widgg Newest 'ffmpeg' Questions - Stack Overflow
  I'm trying to convert audio streams to AAC in C++. FFplay plays everything fine (now) but VLC still has problems with one particular situation: 5.1(side). FFplay only plays it if I filter 5.1(side) to 5.1. Filtering to stereo or mono works well and as expected. My setup right now is: send packet receive audio AVFrame apply filter resample to produce output AVFrame with 1024 samples (required by AAC) send new audio frame receive audio packet Weirdly enough, using FFmpeg's CLI converts my file properly. ffmpeg -i (...)
• 02:04
  FFMPEG HLS stream for Android and IOS - Poda Newest 'ffmpeg' Questions - Stack Overflow
  I'm trying to stream to mobile devices with ffmpeg and apache2.2 but I haven't been successful. I used this command to create the segments and the playlist: ffmpeg -i http://x.x.x.x:8080 -codec:v libx264 -r 25 -pix_fmt yuv420p -profile:v baseline -level 3 -b:v 500k -s 640x480 -codec:a aac -strict experimental -ac 2 -b:a 128k -movflags faststart -flags -global_header -map 0 -f hls -hls_time 10 -hls_list_size 5 -hls_allow_cache 0 -sc_threshold 0 -hls_flags delete_segments -hls_segment_filename out%05d.ts list.m3u8 The source is a http stream which (...)