34 votes
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How to downsample 4k to 1080p using ffmpeg while maintaining the quality?

The default settings for ffmpeg are very low quality, and since you don't specify any codec or quality parameters it's just using the defaults (I don't know why the devs don't fix that because it ...
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  • 13.4k
28 votes
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Can I set the start number for image sequence output?

The image sequence muxer has a start number option, so ffmpeg -i video.webm -start_number 98 image-%03d.png
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  • 30.2k
12 votes
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Big difference in the video file size after the conversion (.mov to .mp4)

Let me explain you from scratch. MOV, MP4, AVI, MKV etc all these are just containers, It is just kind of wrapper which contains audio, video, text, metadata file together as one file. It does not ...
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8 votes
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Video converted by FFMPEG has a different duration, why?

Hope this explanation is what you're looking for: When you transcode to an encoding such as H.264 (MPEG-4 part 10) you necessarily also resample the video, that's part of H.264 compression technique. ...
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  • 486
8 votes
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Does transcoding always mean quality loss?

Generally, H.264 and H.265 (as well as others like VP9) are lossy codecs, at least in their default settings with most encoders. This means that whenever you re-encode from one to another (or even in ...
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  • 955
7 votes
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Apply custom lut via ffmpeg?

You may want to use FFMPEG's lut3d filter. It requires you to provide a look-up table (a *.cube file). For example, if you have an ARRI camera you can generate these files using ARRI Color Tool or ...
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6 votes
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Converting video with different resolutions slightly affects in file size, why?

You are using the same bitrate for each video. The bitrate determines how much data is used per second. The resolution has nothing to do with how much data is used, it only impacts the number of ...
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  • 19.2k
6 votes
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FFMPEG convert video with multiple audio streams?

If you copied your command there then your issue is probably -acodec:0 mp. That should be -acodec:0 mp3. You can just use -c:a mp3 to apply the encoding options to all audio tracks at once, no need ...
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  • 7,099
6 votes
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FFMPEG stop converting from TrueHD to PCM

The WAV header is typically 32-bits. Your output will need 64 bits. ffmpeg -i source.thd -c:a pcm_s24le -ar 48000 -rf64 auto output.wav
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  • 30.2k
6 votes
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Convert video with ffmpeg to have the same quality

The differences between your "works" and "doesn't work" examples are: resolution framerate Codec Tag Codec Level and you can set these using ffmpeg: ffmpeg.exe -i /temp/input.mp4 -c:v mpeg4 -level ...
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  • 176
5 votes

Quality of VHS converted to DVD

One big loss in converting VHS to DVD arises from going through the composite domain. Both VHS and MPEG2 use a separated chroma paradigm -- on the VHS tape are two signals, essentially luma and ...
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  • 4,654
5 votes
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Loss of quality while adding subtitle via FFmpeg

As you are hardcoding subtitles, the video (with the subtitles added) will be re-encoded. You can use the CRF rate control method to modulate the quality of the output. So, start with ffmpeg -i ...
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  • 30.2k
5 votes
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Problem converting TS to MP4 container with ffmpeg

Update: The VLC TS is malformed. First run ffmpeg -i vlc-output.ts -c copy ffmpeg-output.ts and then ffmpeg -i ffmpeg-output.ts -c copy working.mp4 The main thing that looks off is the timebase ...
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  • 30.2k
5 votes

Easily convert & archive a bunch of low res Video CD DAT files MPEG 1/2 to newer better format such as MKV or others?

Using ffmpeg, a free command-line tool, you can convert these DATs to MP4 (or MKV): ffmpeg -i input.dat -c:v libx264 -crf 20 -c:a aac -b:a 128k -movflags +faststart output.mp4 Your VLC output doesn'...
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  • 30.2k
4 votes

How to digitise old NTSC home videos for highest quality (with PAL player)?

As far as deinterlacing: With a good deinterlacer (QTGMC, or at least ffmpeg's yadif=3,mcdeint=2), you can get smooth video at 60000/1001 (NTSC) fps. If your source has quick motions that you'd like ...
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  • 2,618
4 votes

How can I efficiently convert MOV / MPEG-4 files for long term storage?

Although @stib's advice is sound, I disagree with "to get an appreciable size reduction you would have to throw away a lot of quality". Cameras have to compress on-the-fly, so they use constrained ...
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  • 30.2k
4 votes
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mplayer/ffmpeg How to set caca filter's output size

Found. Caca library is driven mostly by environment variables rather than filter params. export CACA_GEOMETRY=200x78 mplayer -vo caca $INPUT
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4 votes
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ffmpeg to convert and merge 3 videos to a single widescreen video

Quality-wise, it's better to use the original MOVs, but if the MP4-based stacking looks ok, that's the final arbiter. ffmpeg -i left.mov -i centre.mov -i right.mov -filter_complex "[0:v:0][1:v:0][2:...
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  • 30.2k
4 votes
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Lossless convert 3gp video to mp4 using ffmpeg

If the codecs of your input file are already h264 and aac for video and audio, respectively, you can just copy without decoding and encoding again. ffmpeg -i input.3gp -c:v copy -c:a copy output.mp4 ...
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  • 176
3 votes

Converting from 3/4" video to digital.

Assuming DVD quality would be enough, you may consider archiving 720p mpeg-4 files with a bitrate of 2 Mbits, which would equate roughly to 1 hour = 1 GB data. That would mean 27,000 hours = 27,000 ...
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  • 131
3 votes

How to convert a .m4v video/audio file to .mp4 on Windows-7, for free

Somewhat of an duplicate of: Can I manually change an .mp4 to .m4v by changing the extension in the Finder (mac) or explorer (win)? MP4 and M4V are essentially the exact same thing, M4V is usually ...
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  • 7,099
3 votes

What is the most lossless way to rip a laserdisc to a Mac?

A lot of these answers seem somewhat misleading unfortunately. Forget about getting a capture card. Practically every one has AGC. AGC is very similar to macrovision, except it's superimposed onto ...
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3 votes
Accepted

How can I convert large jpgs (15000 x 10840px) to video?

That's way more than h.264 can handle. The maximum resolution for h.264 is 4096×2304 with Level 5.1 or 5.2. http://en.wikipedia.org/wiki/H.264#Levels There are lossless codecs who can theoretically ...
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  • 7,099
3 votes

Can video frame size be increased?

There are a few problems here that need to be addressed. First, the pitch shot is vertically oriented or "portrait" (vs landscape). This is considered very, very bad practice. This is a huge and ...
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  • 19.2k
3 votes

How can I reduce the size of a webm to 2MB?

Use Avanti with ffmpeg. The former has a job control manager where you drop in multiple files at once and go. You can find webm encoding guide for ffmpeg here: http://trac.ffmpeg.org/wiki/Encode/VP8 ...
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  • 30.2k
3 votes
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Why does VLC player convert a 4-minute mp4 to a 4-hour webm?

Yes, it seems to be a problem of generated timecode. See https://trac.videolan.org/vlc/ticket/12713#no1 Switch to ffmpeg (with a GUI like Avanti) to avoid this issue. My answer to an earlier webm ...
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  • 30.2k
3 votes
Accepted

Convert resolution 4096x2304 to 3840x2160 keeping the quality the same

Judge based on the quality rather than the bitrate value. Use CRF mode encoding and if the quality isn't what you can accept, decrease the CRF value. ffmpeg -i "%%a" -s 3840x2610 -c:v libx264 -crf 18 ...
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  • 30.2k
3 votes
Accepted

convert horizontal side by side to vertically stacked 3D video

Just integrate all filtering into one command: ffmpeg -i input.mp4 \ -filter_complex "[0:v]crop=in_w/2:in_h:0:0 [top]; \ [0:v]crop=in_w/2:in_h:in_w/2:0[bottom]; \ [top][bottom]vstack[outv]" \ -map "[...
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  • 30.2k
3 votes
Accepted

what graphics card features effect NVIDIA NVENC hardware encoding speed?

There are two main features in NVIDIA NVENC encoding: Video memory if you need to transcode many streams. NVENC SIP - than better this SIP than better encoding performance is. It depends on GPU. You ...
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3 votes
Accepted

Video format can't be played or converted

Use this ffmpeg* command: ffmpeg -i "20151105-175532.dad" -c:v copy "20151105-175532.mp4" *get 32-bit static build.
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  • 30.2k

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