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Sep
3
answered How to display uncompressed gray video?
Aug
26
answered Output ffmpeg to certain format
Aug
16
comment dividing a video clip by 4 areas
See the documentation for the full crop syntax. ffmpeg.org/ffmpeg-filters.html#crop
Aug
16
answered dividing a video clip by 4 areas
Aug
15
comment Converting avi to mov (pro res format) using ffmpeg
Looks ok, although normally the frame rate (-r) is specified in the container and you shouldn't need to change it. You shouldn't need to set the number of samples per audio packet either. What is the issue that you are encountering?
Aug
13
comment Put loudness of many video files to the same level
Are you using a program to edit/encode the videos? If so then look for a normalize option (ideally EBU R128 loudness normalization) in that program. If you don't want to re-encode anything, many formats have a way to add a tag that asks the player to adjust the gain by a specified amount.
Aug
12
answered Appending MP4s loses sound from second file
Jul
16
awarded  Yearling
Jul
15
answered FFMPEG image sequence with various durations
Jul
11
comment FFmpeg: image intro
You can use ffprobe to get the dimensions and duration first if you don't already know them. Insert scale=1280x720, before the intro fade-out if you want to scale the intro to those dimensions. If you want to fade to an outro I suggest overlaying the outro over the main video and fade it in, so that you won't need an alpha channel on your main video. Use the duration to compute the time of the fade and its -itsoffset. Or use the concat filter if you don't care about fading and just want a jump cut.
Jul
6
comment Chrome and Safari show the same behavior on OS X
Have you disabled Javascript, Flash, or cookies? Those links work for me if Javascript is on, but do nothing if it is off.
Jul
6
answered Chrome and Safari show the same behavior on OS X
Jul
6
answered FFmpeg filter to rotate image through arbitrary angle
Jul
4
comment ffmpeg does not apply watermark on first generated frame (wm is applied on all other frames)
@JohnSmith: In general, movie= provides multiple frames. It has to start at some time. You could use the setpts filter to shift the movie= to start earlier, if you knew how much to shift. But removing the negative portions with select is better since the start frame will then be closer to what was requested.
Jul
3
answered ffmpeg does not apply watermark on first generated frame (wm is applied on all other frames)
Jun
24
comment Double deinterlace with full motion - ffmpeg + yadif 50i-50p 60i-60p
Are you sure that your input is interlaced? You can use ffmpeg -i input.m2t -filter:v idet -f null - to analyze it for frames that appear to be top-frame-first interlaced, bottom-frame-first interlaced, or progressive.
Jun
22
comment Double deinterlace with full motion - ffmpeg + yadif 50i-50p 60i-60p
yadif=1 works for me: twice as many frames and each is different
Jun
20
comment Extracting wav from mp4 while preserving the highest possible quality
BTW you could also ask it to resample at a higher rate, but that would just increase the file size and not the quality, so there's not much point in that unless you need a specific sample rate.
Jun
20
comment Extracting wav from mp4 while preserving the highest possible quality
The sample rate will be the same as that of the input. Because it is uncompressed, the bitrate for the wav file is simply the sample rate × sample size × number of channels. If you wanted to reduce the quality you can ask ffmpeg to resample it to a lower rate, change it to 8-bit PCM, or downmix to mono, but it does not do that by default.
Jun
20
answered FFMPEG mp4 instead of flv