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List of compatible distributions
26 avril 2011, parThe table below is the list of Linux distributions compatible with the automated installation script of MediaSPIP. Distribution nameVersion nameVersion number Debian Squeeze 6.x.x Debian Weezy 7.x.x Debian Jessie 8.x.x Ubuntu The Precise Pangolin 12.04 LTS Ubuntu The Trusty Tahr 14.04
If you want to help us improve this list, you can provide us access to a machine whose distribution is not mentioned above or send the necessary fixes to add (...) -
Publier sur MédiaSpip
13 juin 2013Puis-je poster des contenus à partir d’une tablette Ipad ?
Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir -
Gestion des droits de création et d’édition des objets
8 février 2011, parPar défaut, beaucoup de fonctionnalités sont limitées aux administrateurs mais restent configurables indépendamment pour modifier leur statut minimal d’utilisation notamment : la rédaction de contenus sur le site modifiables dans la gestion des templates de formulaires ; l’ajout de notes aux articles ; l’ajout de légendes et d’annotations sur les images ;
Sur d’autres sites (8498)
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Is there a way to extract frames from a video file using ffmpeg to memory and make some manipulation on each frame ?
28 octobre 2022, par Rojer BriefThe goal is to extract each time a frame from the video file then make histogram from the image and then to move to the next frame. this way all the frames.


The frames extraction and the histogram manipulation is working fine when the frames have saved as images on the hard disk. but now i want to do it all in memory.


to extract the frames i'm using ffmpeg because i think it's fast enough :


ffmpeg -r 1 -i MyVid.mp4 -r 1 "$filename%03d.png


for now i'm using the ffmpeg in command prompt window.


with this command it will save on the hard disk over 65000 images(frames).
but instead saving them on the hard disk i wonder if i can make the histogram manipulation on each frame in memory instead saving all the 65000 frames to the hard disk.


then i want to find specific images using the histogram and save to the hard disk this frames.


the histogram part for now is also using files from the hard disk and not from the memory :


private void btnLoadHistogram_Click(object sender, System.EventArgs e)
 {
 string[] files = Directory.GetFiles(@"d:\screenshots\", "*.jpg");

 for (int i = 0; i < files.Length; i++)
 {
 sbInfo.Text = "Loading image";
 if (pbImage.Image != null)
 pbImage.Image.Dispose();

 pbImage.Image = Image.FromFile(files[i]);//txtFileName.Text);

 Application.DoEvents();

 sbInfo.Text = "Computing histogram";
 long[] myValues = GetHistogram(new Bitmap(pbImage.Image));

 Histogram.DrawHistogram(myValues);

 sbInfo.Text = ""; 
 } 
 }

 public long[] GetHistogram(System.Drawing.Bitmap picture)
 {
 long[] myHistogram = new long[256];

 for (int i=0;i3;
 myHistogram[Temp]++;
 }

 return myHistogram;
 }


and the code of the class of the constrol HistogramaDesenat :


using System;
using System.Collections;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Windows.Forms;

namespace Histograma
{
 /// <summary>
 /// Summary description for HistogramaDesenat.
 /// </summary>
 public class HistogramaDesenat : System.Windows.Forms.UserControl
 {
 /// <summary> 
 /// Required designer variable.
 /// </summary>
 private System.ComponentModel.Container components = null;

 public HistogramaDesenat()
 {
 // This call is required by the Windows.Forms Form Designer.
 InitializeComponent();

 // TODO: Add any initialization after the InitializeComponent call

 this.Paint += new PaintEventHandler(HistogramaDesenat_Paint);
 this.Resize+=new EventHandler(HistogramaDesenat_Resize);
 }

 /// <summary> 
 /// Clean up any resources being used.
 /// </summary>
 protected override void Dispose( bool disposing )
 {
 if( disposing )
 {
 if(components != null)
 {
 components.Dispose();
 }
 }
 base.Dispose( disposing );
 }

 #region Component Designer generated code
 /// <summary> 
 /// Required method for Designer support - do not modify 
 /// the contents of this method with the code editor.
 /// </summary>
 private void InitializeComponent()
 {
 // 
 // HistogramaDesenat
 // 
 this.Font = new System.Drawing.Font("Tahoma", 8.25F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((System.Byte)(0)));
 this.Name = "HistogramaDesenat";
 this.Size = new System.Drawing.Size(208, 176);
 }
 #endregion

 private void HistogramaDesenat_Paint(object sender, PaintEventArgs e)
 {
 if (myIsDrawing)
 {

 Graphics g = e.Graphics;
 Pen myPen = new Pen(new SolidBrush(myColor),myXUnit);
 //The width of the pen is given by the XUnit for the control.
 for (int i=0;i/We draw each line 
 g.DrawLine(myPen,
 new PointF(myOffset + (i*myXUnit), this.Height - myOffset), 
 new PointF(myOffset + (i*myXUnit), this.Height - myOffset - myValues[i] * myYUnit));

 //We plot the coresponding index for the maximum value.
 if (myValues[i]==myMaxValue)
 {
 SizeF mySize = g.MeasureString(i.ToString(),myFont);

 g.DrawString(i.ToString(),myFont,new SolidBrush(myColor),
 new PointF(myOffset + (i*myXUnit) - (mySize.Width/2), this.Height - myFont.Height ),
 System.Drawing.StringFormat.GenericDefault);
 }
 }

 //We draw the indexes for 0 and for the length of the array beeing plotted
 g.DrawString("0",myFont, new SolidBrush(myColor),new PointF(myOffset,this.Height - myFont.Height),System.Drawing.StringFormat.GenericDefault);
 g.DrawString((myValues.Length-1).ToString(),myFont, 
 new SolidBrush(myColor),
 new PointF(myOffset + (myValues.Length * myXUnit) - g.MeasureString((myValues.Length-1).ToString(),myFont).Width,
 this.Height - myFont.Height),
 System.Drawing.StringFormat.GenericDefault);

 //We draw a rectangle surrounding the control.
 g.DrawRectangle(new System.Drawing.Pen(new SolidBrush(Color.Black),1),0,0,this.Width-1,this.Height-1);
 }

 }

 long myMaxValue;
 private long[] myValues;
 private bool myIsDrawing;

 private float myYUnit; //this gives the vertical unit used to scale our values
 private float myXUnit; //this gives the horizontal unit used to scale our values
 private int myOffset = 20; //the offset, in pixels, from the control margins.

 private Color myColor = Color.Black;
 private Font myFont = new Font("Tahoma",10);

 [Category("Histogram Options")]
 [Description ("The distance from the margins for the histogram")]
 public int Offset
 {
 set
 {
 if (value>0)
 myOffset= value;
 }
 get
 {
 return myOffset;
 }
 }

 [Category("Histogram Options")]
 [Description ("The color used within the control")]
 public Color DisplayColor
 {
 set
 {
 myColor = value;
 }
 get
 {
 return myColor;
 }
 }

 /// <summary>
 /// We draw the histogram on the control
 /// </summary>
 /// The values beeing draw
 public void DrawHistogram(long[] Values)
 {
 myValues = new long[Values.Length];
 Values.CopyTo(myValues,0);

 myIsDrawing = true;
 myMaxValue = getMaxim(myValues);

 ComputeXYUnitValues();

 this.Refresh();
 }

 /// <summary>
 /// We get the highest value from the array
 /// </summary>
 /// The array of values in which we look
 /// <returns>The maximum value</returns>
 private long getMaxim(long[] Vals)
 {
 if (myIsDrawing)
 {
 long max = 0;
 for (int i=0;i max)
 max = Vals[i];
 }
 return max;
 }
 return 1;
 }

 private void HistogramaDesenat_Resize(object sender, EventArgs e)
 {
 if (myIsDrawing)
 {
 ComputeXYUnitValues();
 }
 this.Refresh();
 }

 private void ComputeXYUnitValues()
 {
 myYUnit = (float) (this.Height - (2 * myOffset)) / myMaxValue;
 myXUnit = (float) (this.Width - (2 * myOffset)) / (myValues.Length-1);
 }
 }
}


so in the end this is what i want to do :


- 

-
extract the frames from the video file in memory using the ffmpeg.


-
instead using Directory.GetFiles i want to make the histogram manipulation on each frame from the memory that is extracted by the ffmpeg.


-
each extracted frame image to use the histogram to find if there is a lightning(weather lightning) in the image.


-
if there is a lightning save the frame image to the hard disk.












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How do I mux both raw h264 and pcm to video container(like mp4) in mediacodec ?
21 février 2019, par geeeekI have a raw h264 file, raw pcm file.
I try to make video container(like mp4) using android mediacodec.
Is it possible ? I did its work in ffmepg, I couldn’t find solution without retranscoding of h264. Most of them use surface view.
Summary, I want that (pcm => ac3) + h264 => mp4. without retranscoding of h264.
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Anomalie #3608 (Nouveau) : Tables de la base de données indispo depuis l’espace privé quand le pré...
29 novembre 2015, par Franck DalotBonjour
SPIP 3.1.0-rc [22601]
Php 5.4.45Lorsque l’on active le menu dev via en cochant la case "ecrire/ ?exec=configurer_preferences"
et que l’on demande à voir les tables dans un site donc le préfix des tables n’est pas "spip" cela ne fonctionne pas, si l’on coche sur le nom d’une table.
Par contre, cela fonctionne si dans l’URL je tape : ecrire/ ?exec=vertebres&table=spip_articles sauf que sur la page, cela écris "spip_articles" au lieu de "spip2_articles"
Dans le cas présent, le préfix est "spip2"A savoir que cela fonctionnait en SPIP 3.1.0-beta [22455] avec un site dont le préfix est "spip1"
Voir copies d’écran
Franck
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