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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 -
Librairies et logiciels spécifiques aux médias
10 décembre 2010, parPour un fonctionnement correct et optimal, plusieurs choses sont à prendre en considération.
Il est important, après avoir installé apache2, mysql et php5, d’installer d’autres logiciels nécessaires dont les installations sont décrites dans les liens afférants. Un ensemble de librairies multimedias (x264, libtheora, libvpx) utilisées pour l’encodage et le décodage des vidéos et sons afin de supporter le plus grand nombre de fichiers possibles. Cf. : ce tutoriel ; FFMpeg avec le maximum de décodeurs et (...) -
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 (...)
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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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ffmpeg encoding leaves me with blank space at the end where the video pauses and there is nothing ahead
6 novembre 2022, par Nisarg DesaiI was trying to slice some of the video being played and clip it in mpv.net using a .lua script which uses ffmpeg to encode the webm output. ffmpeg sometimes leaves some seconds blank and without any video/audio ahead while clipping from source. Is there any solution to this ?


The code for the script is given below (was taken from here https://github.com/occivink/mpv-scripts) :


local utils = require "mp.utils"
local msg = require "mp.msg"
local options = require "mp.options"

local ON_WINDOWS = (package.config:sub(1,1) ~= "/")

local start_timestamp = nil
local profile_start = ""

-- implementation detail of the osd message
local timer = nil
local timer_duration = 2

-- folder creation if it doesnt exist
function exists(file)
 local ok, err, code = os.rename(file, file)
 if not ok then
 if code == 13 then
 return true
 end
 end
 return ok, err
end

--- Check if a directory exists in this path
function create_dir(path)
 local dir = "\"" .. path .. "\""
 if not exists(path .."/") then
 os.execute("mkdir " .. dir)
 end
end

function append_table(lhs, rhs)
 for i = 1,#rhs do
 lhs[#lhs+1] = rhs[i]
 end
 return lhs
end

function file_exists(name)
 local f = io.open(name, "r")
 if f ~= nil then
 io.close(f)
 return true
 else
 return false
 end
end

function get_extension(path)
 local candidate = string.match(path, "%.([^.]+)$")
 if candidate then
 for _, ext in ipairs({ "mkv", "webm", "mp4", "avi" }) do
 if candidate == ext then
 return candidate
 end
 end
 end
 return "mkv"
end

function get_output_string(dir, format, input, extension, title, from, to, profile)
 local res = utils.readdir(dir)
 if not res then
 return nil
 end
 local files = {}
 for _, f in ipairs(res) do
 files[f] = true
 end
 local output = format
 output = string.gsub(output, "$f", function() return input end)
 output = string.gsub(output, "$t", function() return title end)
 output = string.gsub(output, "$s", function() return seconds_to_time_string(from, true) end)
 output = string.gsub(output, "$e", function() return seconds_to_time_string(to, true) end)
 output = string.gsub(output, "$d", function() return seconds_to_time_string(to-from, true) end)
 output = string.gsub(output, "$x", function() return extension end)
 output = string.gsub(output, "$p", function() return profile end)
 if ON_WINDOWS then
 output = string.gsub(output, "[/\\|<>?:\"*]", "_")
 end
 if not string.find(output, "$n") then
 return files[output] and nil or output
 end
 local i = 1
 while true do
 local potential_name = string.gsub(output, "$n", tostring(i))
 if not files[potential_name] then
 return potential_name
 end
 i = i + 1
 end
end

function get_video_filters()
 local filters = {}
 for _, vf in ipairs(mp.get_property_native("vf")) do
 local name = vf["name"]
 name = string.gsub(name, '^lavfi%-', '')
 local filter
 if name == "crop" then
 local p = vf["params"]
 filter = string.format("crop=%d:%d:%d:%d", p.w, p.h, p.x, p.y)
 elseif name == "mirror" then
 filter = "hflip"
 elseif name == "flip" then
 filter = "vflip"
 elseif name == "rotate" then
 local rotation = vf["params"]["angle"]
 -- rotate is NOT the filter we want here
 if rotation == "90" then
 filter = "transpose=clock"
 elseif rotation == "180" then
 filter = "transpose=clock,transpose=clock"
 elseif rotation == "270" then
 filter = "transpose=cclock"
 end
 end
 filters[#filters + 1] = filter
 end
 return filters
end

function get_input_info(default_path, only_active)
 local accepted = {
 video = true,
 audio = not mp.get_property_bool("mute"),
 sub = mp.get_property_bool("sub-visibility")
 }
 local ret = {}
 for _, track in ipairs(mp.get_property_native("track-list")) do
 local track_path = track["external-filename"] or default_path
 if not only_active or (track["selected"] and accepted[track["type"]]) then
 local tracks = ret[track_path]
 if not tracks then
 ret[track_path] = { track["ff-index"] }
 else
 tracks[#tracks + 1] = track["ff-index"]
 end
 end
 end
 return ret
end

function seconds_to_time_string(seconds, full)
 local ret = string.format("%02d:%02d.%03d"
 , math.floor(seconds / 60) % 60
 , math.floor(seconds) % 60
 , seconds * 1000 % 1000
 )
 if full or seconds > 3600 then
 ret = string.format("%d:%s", math.floor(seconds / 3600), ret)
 end
 return ret
end

function start_encoding(from, to, settings)
 local args = {
 settings.ffmpeg_command,
 "-loglevel", "panic", "-hide_banner",
 }
 local append_args = function(table) args = append_table(args, table) end

 local path = mp.get_property("path")
 local is_stream = not file_exists(path)
 if is_stream then
 path = mp.get_property("stream-path")
 end

 local track_args = {}
 local start = seconds_to_time_string(from, false)
 local input_index = 0
 for input_path, tracks in pairs(get_input_info(path, settings.only_active_tracks)) do
 append_args({
 "-ss", start,
 "-i", input_path,
 })
 if settings.only_active_tracks then
 for _, track_index in ipairs(tracks) do
 track_args = append_table(track_args, { "-map", string.format("%d:%d", input_index, track_index)})
 end
 else
 track_args = append_table(track_args, { "-map", tostring(input_index)})
 end
 input_index = input_index + 1
 end

 append_args({"-to", tostring(to-from)})
 append_args(track_args)

 -- apply some of the video filters currently in the chain
 local filters = {}
 if settings.preserve_filters then
 filters = get_video_filters()
 end
 if settings.append_filter ~= "" then
 filters[#filters + 1] = settings.append_filter
 end
 if #filters > 0 then
 append_args({ "-filter:v", table.concat(filters, ",") })
 end

 -- split the user-passed settings on whitespace
 for token in string.gmatch(settings.codec, "[^%s]+") do
 args[#args + 1] = token
 end

 -- path of the output
 local output_directory = mp.get_property("options/screenshot-directory")
 -- local checkbool = exists(output_directory.."/")
 -- mp.osd_message("" .. type(checkbool), timer_duration)
 -- if not checkbool then 
 -- os.execute("mkdir" .. output_directory)
 -- end
 if output_directory == "" then
 if is_stream then
 output_directory = "."
 else
 output_directory, _ = utils.split_path(path)
 end
 else
 output_directory = string.gsub(output_directory, "^~", os.getenv("HOME") or "~")
 end
 local input_name = mp.get_property("filename/no-ext") or "encode"
 local title = mp.get_property("media-title")
 local extension = get_extension(path)
 local output_name = get_output_string(output_directory, settings.output_format, input_name, extension, title, from, to, settings.profile)
 if not output_name then
 mp.osd_message("Invalid path " .. output_directory)
 return
 end
 args[#args + 1] = utils.join_path(output_directory, output_name)

 if settings.print then
 local o = ""
 -- fuck this is ugly
 for i = 1, #args do
 local fmt = ""
 if i == 1 then
 fmt = "%s%s"
 elseif i >= 2 and i <= 4 then
 fmt = "%s"
 elseif args[i-1] == "-i" or i == #args or args[i-1] == "-filter:v" then
 fmt = "%s '%s'"
 else
 fmt = "%s %s"
 end
 o = string.format(fmt, o, args[i])
 end
 print(o)
 end
 if settings.detached then
 utils.subprocess_detached({ args = args })
 else
 local res = utils.subprocess({ args = args, max_size = 0, cancellable = false })
 if res.status == 0 then
 mp.osd_message("Finished encoding succesfully")
 else
 mp.osd_message("Failed to encode, check the log")
 end
 end
end

function clear_timestamp()
 timer:kill()
 start_timestamp = nil
 profile_start = ""
 mp.remove_key_binding("encode-ESC")
 mp.remove_key_binding("encode-ENTER")
 mp.osd_message("", 0)
end

function set_timestamp(profile)
 if not mp.get_property("path") then
 mp.osd_message("No file currently playing")
 return
 end
 if not mp.get_property_bool("seekable") then
 mp.osd_message("Cannot encode non-seekable media")
 return
 end
 create_dir(mp.get_property("options/screenshot-directory"))
 if not start_timestamp or profile ~= profile_start then
 profile_start = profile
 start_timestamp = mp.get_property_number("time-pos")
 local msg = function()
 mp.osd_message(
 string.format("encode [%s]: waiting for end timestamp", profile or "default"),
 timer_duration
 )
 end
 msg()
 timer = mp.add_periodic_timer(timer_duration, msg)
 mp.add_forced_key_binding("ESC", "encode-ESC", clear_timestamp)
 mp.add_forced_key_binding("ENTER", "encode-ENTER", function() set_timestamp(profile) end)
 else
 local from = start_timestamp
 local to = mp.get_property_number("time-pos")
 if to <= from then
 mp.osd_message("Second timestamp cannot be before the first", timer_duration)
 timer:kill()
 timer:resume()
 return
 end
 clear_timestamp()
 mp.osd_message(string.format("Encoding from %s to %s"
 , seconds_to_time_string(from, false)
 , seconds_to_time_string(to, false)
 ), timer_duration)
 -- include the current frame into the extract
 local fps = mp.get_property_number("container-fps") or 30
 to = to + 1 / fps / 2
 local settings = {
 detached = false,
 container = "",
 only_active_tracks = false,
 preserve_filters = true,
 append_filter = "",
 codec = "-c:v libvpx-vp9 -lossless 1 -b:v 1000k -deadline good",
 output_format = "$f_$n.webm",
 output_directory = "",
 ffmpeg_command = "ffmpeg",
 print = true,
 }
 if profile then
 options.read_options(settings, profile)
 if settings.container ~= "" then
 msg.warn("The 'container' setting is deprecated, use 'output_format' now")
 settings.output_format = settings.output_format .. "." .. settings.container
 end
 settings.profile = profile
 else
 settings.profile = "default"
 end 
 start_encoding(from, to, settings)
 end
end

mp.add_key_binding(nil, "set-timestamp", set_timestamp)


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Localization : Add Hindi translation (#2453)
11 novembre 2022, par saurabhsharma2uLocalization : Add Hindi translation (#2453)
* Localisation : Update Hindi (India) translation
* Hindi Translation for Step Method
* HIndi-India Local messages for additional method
* file rename as per ISO 639-1 format
* removed duplicate message, causing the test fail
* removed duplicate "cifES" error message
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