is there any command convert 720p video to lower bitrate 480p using ffmpeg CMD
		
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	Last edited by grabyea; 28th Sep 2021 at 20:52. 
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	The basic command is: 
 Change the video bitrate (-b:v X) to something lower than the source bitrate. For example, if your source has a video bitrate of 3000k, using "-b:v 1500k" will get a video stream that's half the size of the source video stream (the file may not be half the size because the size of the audio isn't changing).Code:ffmpeg -i source.mp4 -vf scale=-4:480 -c:v libx264 -b:v X -c:a copy output.mp4 
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	bad section. this is Video Streaming Downloading section. 
 for your question is better Video Conversion or Editing section.
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 THANKS its worked 
 
 also check this thread
 https://forum.videohelp.com/threads/403271-convert-ts-to-mp4-using-ffmpeg
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	Indeed. “Video conversion” or “Newbies / General discussions” (no editing issue here).bad section. this is Video Streaming Downloading section.
 for your question is better Video Conversion or Editing section.
 
 Unless you have specific size constraints, it's more efficient to use a CRF setting (“Constant Rate Factor”), which is basically a target quality setting. That way you don't have to guesstimate the optimal bitrate for each video and each set of parameters, the encoder does it on its own, and the quality will be consistent when processing various files with the same CRF setting. (For instance, if a whole season of a television series is processed with the same target bitrate, and some episodes have little action and a good lighting, while others are full of action-packed scenes shot at night with heavy rain, the resulting quality of the latter videos will be significantly worse, because those characteristics intrinsically increase the frames' complexity and therefore the bitrate requirement.) A CRF value of 20 is usually considered a good compromise between compression and quality preservation (a lower value like 18 yields a slightly better quality but larger files, a higher value like 22 yields smaller files but the quality loss is slightly higher — the threshold between what is acceptable and what is egregiously overcompressed is highly variable depending on who you ask). Also you can specify a “preset”, which will affect both the resulting quality and the encoding time. If you're not in a hurry and/or have a powerful computer, using “slower” or “veryslow” should yield smaller files and/or a better encoding quality ; if you have an old computer and/or want to use the file ASAP, using “faster” or “veryfast” should speed up the encoding a great deal, but the compression will be less optimized with regards to the size and/or quality (the default being “medium”, which is supposedly a good compromize between speed / size / quality with a current mid-range machine).ffmpeg -i source.mp4 -vf scale=-4:480 -c:v libx264 -b:v X -c:a copy output.mp4
 Code:ffmpeg -i "source.mp4" -vf scale=-4:480 -c:v libx264 -crf 20 -preset slower -c:a copy output.mp4 Last edited by abolibibelot; 4th Oct 2021 at 13:19. 
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	With "-vf scale=X:Y" the first number (X) is the desired width, the second number (Y) the desired height. If the value is a negative number ffmpeg will automatically calculate the value based on the other dimension but will be rounded to the nearest multiple of -N. Progressive YV12 video requires mod2 widths and heights, interlaced YV12 requires mod 4 heights, mod2 widths. Some players require mod4 for both width and height. I recommend you stick with mod4 to be safe (even though it may give a small aspect ratio error). 
 
 For example, if you start with a 1920x1080 video and downscale to 900 pixels wide with "-vf scale=900:-4" ffmpeg will calculate the height to nearest mod4 value (integer multiple of 4, ie 4, 8, 12, 16, 20...). The perfect height would be 506.25 but the height has to be an integer. The nearest integer is 506 but that is mod2, not mod4 (506/4=126.5). 508 is the nearest mod4 value to 506.25 (508/4=127). That results in about a 1/2 percent aspect ratio error -- but you won't notice that small an error upon viewing the new video.
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	@lomero 
 @jagabo
 
 from last few days if i try to download live strea =m m38 url in streamlink its giving this error but when i uninstall and install streamlink again it only works 1 time and than again eror any idea whats wrong?
 
 Could Not Find C:\Program Files (x86)\Streamlink\Python\VCRUNTIME140.dll.dat
 File "J:\Streamlink\bin\streamlink.exe", line 1
 SyntaxError: Non-UTF-8 code starting with '\x90' in file J:\Streamlink\bin\streamlink.exe on line 1, but no encoding declared; see http://python.org/dev/peps/pep-0263/ for details
 
 i have tried all streamlink version new and
 
 im using this command since long time never had issue but now
 
 streamlink "m3u8 link" best -o video.tsLast edited by grabyea; 24th Nov 2021 at 20:25. 
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	Try (re)installing Microsoft Visual Studio 2015 Runtime: https://www.microsoft.com/en-gb/download/details.aspx?id=48145 
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	This was already explained in post #9. 
 
 replace -vf scale=-4:480 with -vf scale=-4:1080
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	Last edited by grabyea; 5th Nov 2022 at 19:33. 
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	Never allow mod 1 with subsampled chroma (4:1:1, 4:2:0, 4:2:2). I prefer to use mod 4 instead of mod 2 because some old players have problems with mod 2. And interlaced video must be mod 4 vertically. 
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	The scale filter resizes any input size to the specified output size. Once again, I prefer to use mod 4 sizes. 
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