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Video d’abeille en portrait
14 May 2011, by
Updated: February 2012
Language: français
Type: Video
Other articles (46)
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Les formats acceptés
28 January 2010, byLes commandes suivantes permettent d’avoir des informations sur les formats et codecs gérés par l’installation local de ffmpeg :
ffmpeg -codecs ffmpeg -formats
Les format videos acceptés en entrée
Cette liste est non exhaustive, elle met en exergue les principaux formats utilisés : h264 : H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 m4v : raw MPEG-4 video format flv : Flash Video (FLV) / Sorenson Spark / Sorenson H.263 Theora wmv :
Les formats vidéos de sortie possibles
Dans un premier temps on (...) -
Ajouter notes et légendes aux images
7 February 2011, byPour pouvoir ajouter notes et légendes aux images, la première étape est d’installer le plugin "Légendes".
Une fois le plugin activé, vous pouvez le configurer dans l’espace de configuration afin de modifier les droits de création / modification et de suppression des notes. Par défaut seuls les administrateurs du site peuvent ajouter des notes aux images.
Modification lors de l’ajout d’un média
Lors de l’ajout d’un média de type "image" un nouveau bouton apparait au dessus de la prévisualisation (...) -
Websites made with MediaSPIP
2 May 2011, byThis page lists some websites based on MediaSPIP.
On other websites (9050)
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avformat/rtpdec_rfc4175: add support for RANGE
11 October 2021, by Limin Wang -
vaapi_encode_h264: Reduce SAR to valid range
28 October 2018, by Mark Thompsonvaapi_encode_h264: Reduce SAR to valid range
The SAR of the input could have a numerator or denominator greater than
2^16 which would then be truncated to a 16-bit integer when written to
the VUI parameters, giving a random result. Instead, reduce the SAR to
the nearest representable fraction.Fixes #7502.
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ffmpeg how to shorten volume range
10 July 2021, by 敬錞 潘I use this command below to get volume information


ffmpeg -i {fileName} -af "volumedetect" -f null -



and get result below:


[Parsed_volumedetect_0 @ 000001b4f9675ec0] mean_volume: -25.1 dB
[Parsed_volumedetect_0 @ 000001b4f9675ec0] max_volume: -4.0 dB
[Parsed_volumedetect_0 @ 000001b4f9675ec0] histogram_4db: 12
[Parsed_volumedetect_0 @ 000001b4f9675ec0] histogram_5db: 72
[Parsed_volumedetect_0 @ 000001b4f9675ec0] histogram_6db: 293
[Parsed_volumedetect_0 @ 000001b4f9675ec0] histogram_7db: 808
[Parsed_volumedetect_0 @ 000001b4f9675ec0] histogram_8db: 2276
[Parsed_volumedetect_0 @ 000001b4f9675ec0] histogram_9db: 5885
[Parsed_volumedetect_0 @ 000001b4f9675ec0] histogram_10db: 13146
[Parsed_volumedetect_0 @ 000001b4f9675ec0] histogram_11db: 26627



I want to shorten volume range to half range like this below


[Parsed_volumedetect_0 @ 000001b4f9675ec0] histogram_6db: ...
[Parsed_volumedetect_0 @ 000001b4f9675ec0] histogram_7db: ...
[Parsed_volumedetect_0 @ 000001b4f9675ec0] histogram_8db: ...
[Parsed_volumedetect_0 @ 000001b4f9675ec0] histogram_9db: ...



How to do it by ffmpeg command?


Update1:


filename.mp3 volume detect is below:


[Parsed_volumedetect_0 @ 00000192cd9adcc0] max_volume: -0.3 dB
[Parsed_volumedetect_0 @ 00000192cd9adcc0] histogram_0db: 32
[Parsed_volumedetect_0 @ 00000192cd9adcc0] histogram_1db: 333
[Parsed_volumedetect_0 @ 00000192cd9adcc0] histogram_2db: 1216
[Parsed_volumedetect_0 @ 00000192cd9adcc0] histogram_3db: 3490
[Parsed_volumedetect_0 @ 00000192cd9adcc0] histogram_4db: 8829
[Parsed_volumedetect_0 @ 00000192cd9adcc0] histogram_5db: 19873



after execute command


ffmpeg -i filename.mp3 -af filename_output.mp3



filename_output.mp3 volume detect is below:


[Parsed_volumedetect_0 @ 0000017af506dd00] max_volume: -0.4 dB
[Parsed_volumedetect_0 @ 0000017af506dd00] histogram_0db: 13
[Parsed_volumedetect_0 @ 0000017af506dd00] histogram_1db: 226
[Parsed_volumedetect_0 @ 0000017af506dd00] histogram_2db: 906
[Parsed_volumedetect_0 @ 0000017af506dd00] histogram_3db: 2688
[Parsed_volumedetect_0 @ 0000017af506dd00] histogram_4db: 7202
[Parsed_volumedetect_0 @ 0000017af506dd00] histogram_5db: 16473



There is no big changes, if I want to shorten more volume range , how to do?