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The Slip - Artworks
26 septembre 2011, par
Mis à jour : Septembre 2011
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Autres articles (109)
-
L’agrémenter visuellement
10 avril 2011MediaSPIP est basé sur un système de thèmes et de squelettes. Les squelettes définissent le placement des informations dans la page, définissant un usage spécifique de la plateforme, et les thèmes l’habillage graphique général.
Chacun peut proposer un nouveau thème graphique ou un squelette et le mettre à disposition de la communauté. -
Ajouter des informations spécifiques aux utilisateurs et autres modifications de comportement liées aux auteurs
12 avril 2011, parLa manière la plus simple d’ajouter des informations aux auteurs est d’installer le plugin Inscription3. Il permet également de modifier certains comportements liés aux utilisateurs (référez-vous à sa documentation pour plus d’informations).
Il est également possible d’ajouter des champs aux auteurs en installant les plugins champs extras 2 et Interface pour champs extras. -
Encoding and processing into web-friendly formats
13 avril 2011, parMediaSPIP automatically converts uploaded files to internet-compatible formats.
Video files are encoded in MP4, Ogv and WebM (supported by HTML5) and MP4 (supported by Flash).
Audio files are encoded in MP3 and Ogg (supported by HTML5) and MP3 (supported by Flash).
Where possible, text is analyzed in order to retrieve the data needed for search engine detection, and then exported as a series of image files.
All uploaded files are stored online in their original format, so you can (...)
Sur d’autres sites (11917)
-
ffmpeg status & quality / cuda (CPU/GPU)
18 avril 2015, par coccoffmpeg am i doing it right ?
So much time has passed since i use ffmpeg to convert clips on my home web server, now that mp4 (h264 & aac) is the current overall standard (works on every console, smartphone, smartTV, pc) i decided to convert my old clips from various digital cameras to to this new container/codecs.
- less space & the same quality.
- compatibility
- support for tags (subler for mac)
after some research i opted for ffmpeg because of various reasons
- commandline (i made my simple web interface with default settings wich i execute with php’s exec)
- the quality/size amount
I read that many expensive video conversion softwares are not able to handle low bitrate videos properly. I also tested some of them and personally i could not find the proper export settings or i was not impressed by the results... some had fixed default export setings, most had a lower video quality at the same filesize. ffmpeg allows me to set the -crf (18-24 usually) and -preset (veryslow, fast..) witch allows me to reduce the filesize drastically mantaining the same
visible quality.Said that i’m using the preset at veryslow.(there is also placebo but the final video file is only 1% smaller in size).
And here is the command i use
ffmpeg
-y //overwrite the file if it exists
-i INPUTFILE // replace with the input file
-metadata title=THETITLE // set a nice title, visible on modern devices
-metadata date=THEDATE // set a nice title, visible on modern devices
-c:v libx264 // use the h264 codec
-crf 21 // try different numbers between 18-26
-preset veryslow // placebo,slow,fast,ultrafast==big file
-tune film // tune it a little
-pix_fmt yuv420p // preferred on most modern devices
-profile:v main // preferred on most modern devices
-level 3.1 // preferred on most modern devices
-refs 4 // preferred on most modern devices
-c:a libfdk_aac // use aac
-metadata:s:a language=eng // set a language, visible on modern devices
-b:a 128k // audio bitrate 128k is like mp3 192k
-ar 48000 // 44100 ... whatever
-ac 2 // audiochannels
-movflags +faststart //move the metadata in the front of the video so it loads faster
OUTPUTFILEsome camcorder clips with m2ts already have the avc/h264 compatible codec so i just copy the stream.
some have the ac3/dolby sorround audio. I convert the audio but keep the ac3 as second audio track mapping the ffmpeg streams.this allows me to watch the mp4 on browsers and mobile devices but i’m able to keep the surround sound to playback on some tv’s, advanced media players or devices like apple tv.not that i’m not happy with the speed (using quad core’s) but i recently read again about cuda opencl and there is also the simple fact that i’m not using other converters than ffmpeg since alot of time.
Is ffmpeg (with the setting i use) a good converter to keep the same video quality than the source reducing the space occupied by and average of 30-40% ?
Is GPU conversion really that bad (cuda .. testing a gtx970) ?
it would be nice to add some more speed to the conversions by using both the gpu and the cpu..but for my understanding they cannot work together ??? and using only gpu is a drastical quality loss...cpu si more precise, gpu is faster in calculation are too imprecise from what i read.. so expensive softwares use cuda only for preview purpose... right ?Is ffmpeg or another software compatible with CPU+GPU encoding ?
i really don’t remember where, but i read that the ffmpeg is not a good videoconverter.i’m really happy with the size/quality, i gained an average of 30% in space with no visible quality loss. With some extra parameters i can adjust some really old analog videos that are deinterlaced in a really bad way.
maybe i could gain more size/quality with another software ???
note : i like ffmpeg.it’s free and it has commandline so i can create my own interface with php html & js and use it on various machines without the need to install it in every device i use. i uplad the idevice clips directly to the ffmpeg server.
btw. : explain the downvotes...
EDIT :
@talonmies ...cuda tag removed :
http://www.nvidia.com/object/cuda_home_new.html
CUDA® is a parallel computing platform and programming model invented
by NVIDIA. It enables dramatic increases in computing performance by
harnessing the power of the graphics processing unit (GPU). With
millions of CUDA-enabled GPUs sold to date, software developers,
scientists and researchers are finding broad-ranging uses for GPU
computing with CUDA. Here are a few examples : - See more at :
http://www.nvidia.com/object/cuda_home_new.html#sthash.dEYaqae7.dpufisn’t cuda the programming model that a theoretical ffmpeg library should support to handle GPU encoding on nvidia cards like the gtx 970 ?? like the badaboom software http://www.geforce.com/games-applications/pc-applications/badaboom-media-converter.
-
Camera app fails on android ffmpeg application
22 mars 2021, par connor449I am trying to run a simple video recorder app on android. The code is below :


package com.example.camera

//import android.R
import android.content.DialogInterface
import android.content.pm.PackageManager
import android.os.Build
import android.os.Bundle
import android.widget.Toast
import androidx.appcompat.app.AlertDialog
import androidx.appcompat.app.AppCompatActivity
import androidx.core.app.ActivityCompat
import androidx.core.content.ContextCompat
import com.arthenica.mobileffmpeg.FFmpeg


const val EXTRA_MESSAGE = "com.example.myfirstapp.MESSAGE"

class MainActivity : AppCompatActivity() {
 override fun onCreate(savedInstanceState: Bundle?) {
 super.onCreate(savedInstanceState)
 setContentView(R.layout.activity_main)
 if (checkPermission()) {
 //main logic or main code
 FFmpeg.execute("-f android_camera -i 0:0 -r 30 -pixel_format bgr0 -t 00:00:05 /sdcard/test.mp4")

 // . write your main code to execute, It will execute if the permission is already given.
 } else {
 requestPermission()
 }
 }

 private fun checkPermission(): Boolean {
 return if (ContextCompat.checkSelfPermission(this, android.Manifest.permission.CAMERA)
 != PackageManager.PERMISSION_GRANTED
 ) {
 // Permission is not granted
 false
 } else true
 }

 private fun requestPermission() {
 ActivityCompat.requestPermissions(
 this, arrayOf(android.Manifest.permission.CAMERA),
 PERMISSION_REQUEST_CODE
 )
 }

 override fun onRequestPermissionsResult(
 requestCode: Int,
 permissions: Array<string>,
 grantResults: IntArray
 ) {
 when (requestCode) {
 PERMISSION_REQUEST_CODE -> if (grantResults.size > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED
 ) {
 Toast.makeText(applicationContext, "Permission Granted", Toast.LENGTH_SHORT)
 .show()

 // main logic
 } else {
 Toast.makeText(applicationContext, "Permission Denied", Toast.LENGTH_SHORT)
 .show()
 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
 if (ContextCompat.checkSelfPermission(this, android.Manifest.permission.CAMERA)
 != PackageManager.PERMISSION_GRANTED
 ) {
 showMessageOKCancel("You need to allow access permissions",
 DialogInterface.OnClickListener { dialog, which ->
 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
 requestPermission()
 }
 })
 }
 }
 }
 }
 }

 private fun showMessageOKCancel(
 message: String,
 okListener: DialogInterface.OnClickListener
 ) {
 AlertDialog.Builder(this@MainActivity)
 .setMessage(message)
 .setPositiveButton("OK", okListener)
 .setNegativeButton("Cancel", null)
 .create()
 .show()
 }

 companion object {
 private const val PERMISSION_REQUEST_CODE = 200
 }
}


</string>

The main command to call the video recorder is here :


FFmpeg.execute("-f android_camera -i 0:0 -r 30 -pixel_format bgr0 -t 00:00:05 /sdcard/test.mp4")


The app opens on my android 10 Motorola G Power. I tap 'allow' for allowing permissions. Then the app crashes and I keep getting this error :


2021-03-22 13:42:51.534 31138-31138/com.example.camera E/AndroidRuntime: FATAL EXCEPTION: main
 Process: com.example.camera, PID: 31138
 java.lang.IllegalStateException: Could not find method sendMessage(View) in a parent or ancestor Context for android:onClick attribute defined on view class com.google.android.material.button.MaterialButton with id 'button2'
 at androidx.appcompat.app.AppCompatViewInflater$DeclaredOnClickListener.resolveMethod(AppCompatViewInflater.java:436)
 at androidx.appcompat.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:393)
 at android.view.View.performClick(View.java:7161)
 at com.google.android.material.button.MaterialButton.performClick(MaterialButton.java:967)
 at android.view.View.performClickInternal(View.java:7133)
 at android.view.View.access$3500(View.java:804)
 at android.view.View$PerformClick.run(View.java:27416)
 at android.os.Handler.handleCallback(Handler.java:883)
 at android.os.Handler.dispatchMessage(Handler.java:100)
 at android.os.Looper.loop(Looper.java:241)
 at android.app.ActivityThread.main(ActivityThread.java:7617)
 at java.lang.reflect.Method.invoke(Native Method)
 at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:941)
2021-03-22 13:42:51.546 31138-31138/com.example.camera I/Process: Sending signal. PID: 31138 SIG: 9


What am I doing wrong ? Please advise.


edit


layout xml


<?xml version="1.0" encoding="utf-8"?>


 

 



-
ffmpeg status & quality / cuda (CPU/GPU)
18 juin 2024, par coccoffmpeg am I doing it right ?


So much time has passed since I use ffmpeg to convert clips on my home web server, now that mp4 (h264 & aac) is the current overall standard (works on every console, smartphone, smartTV, pc) I decided to convert my old clips from various digital cameras to to this new container/codecs.


- 

- less space & the same quality.
- compatibility
- support for tags (subler for mac)








after some research I opted for ffmpeg because of various reasons


- 

- commandline (I made my simple web interface with default settings which I execute with php's exec)
- the quality/size amount






I read that many expensive video conversion software programs are not able to handle low bitrate videos properly. I also tested some of them and personally I could not find the proper export settings or I was not impressed by the results... some had fixed default export settings, most had a lower video quality at the same filesize. ffmpeg allows me to set the -crf (18-24 usually) and -preset (veryslow, fast..) which allows me to reduce the filesize drastically maintaining the same visible quality.


Said that I'm using the preset at very slow (there is also placebo but the final video file is only 1% smaller in size).


And here is the command I use


ffmpeg
-y //overwrite the file if it exists

-i INPUTFILE // replace with the input file

-metadata title=THETITLE // set a nice title, visible on modern devices
-metadata date=THEDATE // set a nice title, visible on modern devices

-c:v libx264 // use the h264 codec
 -crf 21 // try different numbers between 18-26
 -preset veryslow // placebo,slow,fast,ultrafast==big file 
 -tune film // tune it a little
 -pix_fmt yuv420p // preferred on most modern devices
 -profile:v main // preferred on most modern devices
 -level 3.1 // preferred on most modern devices 
 -refs 4 // preferred on most modern devices

-c:a libfdk_aac // use aac
 -metadata:s:a language=eng // set a language, visible on modern devices 
 -b:a 128k // audio bitrate 128k is like mp3 192k
 -ar 48000 // 44100 ... whatever
 -ac 2 // audiochannels
 -movflags +faststart //move the metadata in the front of the video so it loads faster

OUTPUTFILE


Some camcorder clips with m2ts already have the avc/h264 compatible codec so I just copy the stream.

some have the ac3/Dolby surround audio. I convert the audio but keep the ac3 as second audio track mapping the ffmpeg streams. this allows me to watch the mp4 on browsers and mobile devices but I'm able to keep the surround sound to playback on some tv's, advanced media players or devices like apple tv.

Not that I'm not happy with the speed (using quad core's) but I recently read again about cuda opencl and there is also the simple fact that I'm not using other converters than ffmpeg since a lot of time.


Is ffmpeg (with the setting I use) a good converter to keep the same video quality than the source reducing the space occupied by and average of 30-40% ?


Is GPU conversion really that bad (cuda .. testing a gtx970) ?
it would be nice to add some more speed to the conversions by using both the gpu and the cpu..but for my understanding they cannot work together ??? and using only GPU is a drastically quality loss...cpu is more precise, GPU is faster in calculation are too imprecise from what I read.. so expensive software programs use cuda only for preview purpose... right ?


Is ffmpeg or another software compatible with CPU+GPU encoding ?
I really don't remember where, but I read that the ffmpeg is not a good videoconverter.


I'm really happy with the size/quality, I gained an average of 30% in space with no visible quality loss. With some extra parameters i can adjust some really old analog videos that are deinterlaced in a really bad way.




maybe I could gain more size/quality with another software ???




note : I like ffmpeg.it's free and it has commandline so I can create my own interface with php html & js and use it on various machines without the need to install it in every device I use. I upload the idevice clips directly to the ffmpeg server.


EDIT :


@talonmies ...cuda tag removed :


http://www.nvidia.com/object/cuda_home_new.html




CUDA® is a parallel computing platform and programming model invented
by NVIDIA. It enables dramatic increases in computing performance by
harnessing the power of the graphics processing unit (GPU). With
millions of CUDA-enabled GPUs sold to date, software developers,
scientists and researchers are finding broad-ranging uses for GPU
computing with CUDA. Here are a few examples : - See more at :
http://www.nvidia.com/object/cuda_home_new.html#sthash.dEYaqae7.dpuf




isn't cuda the programming model that a theoretical ffmpeg library should support to handle GPU encoding on nvidia cards like the gtx 970 ?? like the badaboom software http://www.geforce.com/games-applications/pc-applications/badaboom-media-converter.


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