Ffmpeg - Revision history

Burger: /* Convert Portion of Video to GIF/MP4 */

2026-04-07T06:29:19Z

Convert Portion of Video to GIF/MP4

← Older revision		Revision as of 02:29, 7 April 2026
Line 152:		Line 152:
	ffmpeg -i video.mp4 -ss 00:03:05 -t 00:00:05.0 output.gif		ffmpeg -i video.mp4 -ss 00:03:05 -t 00:00:05.0 output.gif
	ffmpeg -i video.mp4 -ss 00:03:05 -t 00:00:05.0 output.mp4		ffmpeg -i video.mp4 -ss 00:03:05 -t 00:00:05.0 output.mp4
			===Playback Video at 2x Speed===
			ffmpeg -i input.mp4 -vf "setpts=0.5*PTS" output.mp4
			From: https://ottverse.com/how-to-speed-up-slow-down-video-playback-using-ffmpeg/#How_to_Speed_Up_Video_with_FFmpeg

	==Lower Resolution of Video==		==Lower Resolution of Video==
	$ ffmpeg -i example.mp4 -vf scale=640:480 output.mp4		$ ffmpeg -i example.mp4 -vf scale=640:480 output.mp4

Burger: /* Lower Resolution of Video */

2025-10-30T06:55:02Z

Lower Resolution of Video

← Older revision		Revision as of 02:55, 30 October 2025
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	Here, the -vf option stands for video filter, and the scale=640:480 parameter tells FFmpeg to resize the video to 640 pixels wide and 480 pixels high.		Here, the -vf option stands for video filter, and the scale=640:480 parameter tells FFmpeg to resize the video to 640 pixels wide and 480 pixels high.

	We can also use -1 as a placeholder for either width or height, and FFmpeg automatically calculates the other dimension to preserve the video’s aspect ratio>		We can also use -1 as a placeholder for either width or height, and FFmpeg automatically calculates the other dimension to preserve the video’s aspect ratio.
	$ ffmpeg -i example.mp4 -vf scale=640:-1 output.mp4		$ ffmpeg -i example.mp4 -vf scale=640:-1 output.mp4

Burger: /* Convert Portion of Video to GIF/MP4 */

2025-10-30T06:54:47Z

Convert Portion of Video to GIF/MP4

← Older revision		Revision as of 02:54, 30 October 2025
Line 152:		Line 152:
	ffmpeg -i video.mp4 -ss 00:03:05 -t 00:00:05.0 output.gif		ffmpeg -i video.mp4 -ss 00:03:05 -t 00:00:05.0 output.gif
	ffmpeg -i video.mp4 -ss 00:03:05 -t 00:00:05.0 output.mp4		ffmpeg -i video.mp4 -ss 00:03:05 -t 00:00:05.0 output.mp4
			==Lower Resolution of Video==
			$ ffmpeg -i example.mp4 -vf scale=640:480 output.mp4
			Here, the -vf option stands for video filter, and the scale=640:480 parameter tells FFmpeg to resize the video to 640 pixels wide and 480 pixels high.

			We can also use -1 as a placeholder for either width or height, and FFmpeg automatically calculates the other dimension to preserve the video’s aspect ratio>
			$ ffmpeg -i example.mp4 -vf scale=640:-1 output.mp4

			reference: https://www.baeldung.com/linux/video-downsample-lower-resolution

	===Get Image from Network Stream and Output to Remote Framebuffer Using dd===		===Get Image from Network Stream and Output to Remote Framebuffer Using dd===

Burger: /* Moving the Mov Atom (video metadata) to the Beginning of the Video Will Fix Some Issues With Mono Audio */

2025-10-15T23:42:47Z

Moving the Mov Atom (video metadata) to the Beginning of the Video Will Fix Some Issues With Mono Audio

← Older revision		Revision as of 19:42, 15 October 2025
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	ffmpeg -i 748604-video.mp4 -movflags faststart -c copy output.mp4		ffmpeg -i 748604-video.mp4 -movflags faststart -c copy output.mp4

			This moves the moov-atom metadata to the beginning of the file. And then it plays perfectly:
	</pre>		</pre>

Burger: /* Moving the Mov Atom (video metadata) to the Beginning of the Video Will Fix Some Issues With Mono Audio */

2025-10-15T23:42:09Z

Moving the Mov Atom (video metadata) to the Beginning of the Video Will Fix Some Issues With Mono Audio

@@ Line 298: / Line 298: @@
 ===Moving the Mov Atom (video metadata) to the Beginning of the Video Will Fix Some Issues With Mono Audio===
 Please read the forum thread. This is a bug unique to a 1.36 release, but it is generally useful for MP4 encoding, so I thought I would include it here. Reference: https://forums.zoneminder.com/viewtopic.php?t=34111
 <pre>
 Yes, add movflags=frag_keyframe+empty_moov+faststart to options. The value here is what is used in 1.37. Although I think empty_moov might be deprecated in newer ffmpeg.

Burger: /* Moving the Mov Atom (video metadata) to the Beginning of the Video Will Fix Some Issues With Mono Audio */

2025-10-15T23:41:21Z

Moving the Mov Atom (video metadata) to the Beginning of the Video Will Fix Some Issues With Mono Audio

← Older revision		Revision as of 19:41, 15 October 2025
Line 297:		Line 297:
	https://forums.zoneminder.com/viewtopic.php?p=137922		https://forums.zoneminder.com/viewtopic.php?p=137922
	===Moving the Mov Atom (video metadata) to the Beginning of the Video Will Fix Some Issues With Mono Audio===		===Moving the Mov Atom (video metadata) to the Beginning of the Video Will Fix Some Issues With Mono Audio===
	~~See~~: https://forums.zoneminder.com/viewtopic.php?t=34111		Please read the forum thread. This is a bug unique to a 1.36 release, but it is generally useful for MP4 encoding, so I thought I would include it here. Reference: https://forums.zoneminder.com/viewtopic.php?t=34111
	<pre>		<pre>
	Yes, add movflags=frag_keyframe+empty_moov+faststart to options. The value here is what is used in 1.37. Although I think empty_moov might be deprecated in newer ffmpeg.		Yes, add movflags=frag_keyframe+empty_moov+faststart to options. The value here is what is used in 1.37. Although I think empty_moov might be deprecated in newer ffmpeg.

Burger: /* Moving the Mov Atom (video metadata) to the Beginning of the Video Will Fix Some Issues */

2025-10-15T23:40:29Z

Moving the Mov Atom (video metadata) to the Beginning of the Video Will Fix Some Issues

← Older revision		Revision as of 19:40, 15 October 2025
Line 296:		Line 296:

	https://forums.zoneminder.com/viewtopic.php?p=137922		https://forums.zoneminder.com/viewtopic.php?p=137922
	===Moving the Mov Atom (video metadata) to the Beginning of the Video Will Fix Some Issues===		===Moving the Mov Atom (video metadata) to the Beginning of the Video Will Fix Some Issues With Mono Audio===
	See: https://forums.zoneminder.com/viewtopic.php?t=34111		See: https://forums.zoneminder.com/viewtopic.php?t=34111
	<pre>		<pre>

Burger: /* Unnecessary Encoding of Joining Videos with FFmpeg */

2025-10-15T23:39:10Z

Unnecessary Encoding of Joining Videos with FFmpeg

← Older revision		Revision as of 19:39, 15 October 2025
Line 296:		Line 296:

	https://forums.zoneminder.com/viewtopic.php?p=137922		https://forums.zoneminder.com/viewtopic.php?p=137922
			===Moving the Mov Atom (video metadata) to the Beginning of the Video Will Fix Some Issues===
			See: https://forums.zoneminder.com/viewtopic.php?t=34111
			<pre>
			Yes, add movflags=frag_keyframe+empty_moov+faststart to options. The value here is what is used in 1.37. Although I think empty_moov might be deprecated in newer ffmpeg.
			The default in 1.36 is frag_keyframe+empty_moov.
			</pre>

	==See Also==		==See Also==

Burger: /* Unnecessary Encoding of Joining Videos with FFmpeg */

2025-09-15T00:08:19Z

Unnecessary Encoding of Joining Videos with FFmpeg

← Older revision		Revision as of 20:08, 14 September 2025
Line 294:		Line 294:
	For more details, see:		For more details, see:
	https://forums.zoneminder.com/viewtopic.php?p=137923		https://forums.zoneminder.com/viewtopic.php?p=137923

	https://forums.zoneminder.com/viewtopic.php?p=137922		https://forums.zoneminder.com/viewtopic.php?p=137922

Burger: /* Unnecessary Encoding of Joining Videos with FFmpeg */

2025-09-15T00:03:42Z

Unnecessary Encoding of Joining Videos with FFmpeg

← Older revision		Revision as of 20:03, 14 September 2025
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	===Unnecessary Encoding of Joining Videos with FFmpeg===		===Unnecessary Encoding of Joining Videos with FFmpeg===
	You may think you need a GPU to speed up encoding of videos, if you were to combine them. This is not necessarily true. If you keep the codecs the same, then FFmpeg (or Mencoder) is able to do a type of semi-encode (or transcode) where it will reorganize the MP4 files to join them together, without doing a full re-encode.		You may think you need a GPU to speed up encoding of videos, if you were to combine them. This is not necessarily true. If you keep the codecs the same, then FFmpeg (or Mencoder) is able to do a type of semi-encode (or transcode) where it will reorganize the MP4 files to join them together, without doing a full re-encode.

			For more details, see:
			https://forums.zoneminder.com/viewtopic.php?p=137923
			https://forums.zoneminder.com/viewtopic.php?p=137922

	==See Also==		==See Also==