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Organiser par catégorie
17 mai 2013, parDans MédiaSPIP, une rubrique a 2 noms : catégorie et rubrique.
Les différents documents stockés dans MédiaSPIP peuvent être rangés dans différentes catégories. On peut créer une catégorie en cliquant sur "publier une catégorie" dans le menu publier en haut à droite ( après authentification ). Une catégorie peut être rangée dans une autre catégorie aussi ce qui fait qu’on peut construire une arborescence de catégories.
Lors de la publication prochaine d’un document, la nouvelle catégorie créée sera proposée (...) -
Récupération d’informations sur le site maître à l’installation d’une instance
26 novembre 2010, parUtilité
Sur le site principal, une instance de mutualisation est définie par plusieurs choses : Les données dans la table spip_mutus ; Son logo ; Son auteur principal (id_admin dans la table spip_mutus correspondant à un id_auteur de la table spip_auteurs)qui sera le seul à pouvoir créer définitivement l’instance de mutualisation ;
Il peut donc être tout à fait judicieux de vouloir récupérer certaines de ces informations afin de compléter l’installation d’une instance pour, par exemple : récupérer le (...) -
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
Sur d’autres sites (5722)
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FFmpeg conversion RGB to YUV420 to RGB wrong result
29 août 2020, par sipwizI'm attempting to sort out a video encoding issue and along the way making sure I can convert between pixel formats with FFmpeg. I'm having a problem converting a dummy RGB24 bitmap to YUV420 and back again.


Below is my test program :


#include "Windows.h"

#include <libavcodec></libavcodec>avcodec.h>
#include <libavformat></libavformat>avformat.h>
#include <libavformat></libavformat>avio.h>
#include <libavutil></libavutil>imgutils.h>
#include <libswscale></libswscale>swscale.h>
#include <libavutil></libavutil>time.h>

#define WIDTH 32
#define HEIGHT 32
#define ERROR_LEN 128
#define SWS_FLAGS SWS_BICUBIC

char _errorLog[ERROR_LEN];
void CreateBitmapFile(LPCWSTR fileName, long width, long height, WORD bitsPerPixel, BYTE* bitmapData, DWORD bitmapDataLength);

int main()
{
 printf("FFmpeg Pixel Conversion Test\n");

 av_log_set_level(AV_LOG_DEBUG);

 int w = WIDTH;
 int h = HEIGHT;

 struct SwsContext* rgbToI420Context;
 struct SwsContext* i420ToRgbContext;

 rgbToI420Context = sws_getContext(w, h, AV_PIX_FMT_RGB24, w, h, AV_PIX_FMT_YUV420P, SWS_FLAGS, NULL, NULL, NULL);
 if (rgbToI420Context == NULL) {
 fprintf(stderr, "Failed to allocate RGB to I420 conversion context.\n");
 }

 i420ToRgbContext = sws_getContext(w, h, AV_PIX_FMT_YUV420P, w, h, AV_PIX_FMT_RGB24, SWS_FLAGS, NULL, NULL, NULL);
 if (i420ToRgbContext == NULL) {
 fprintf(stderr, "Failed to allocate I420 to RGB conversion context.\n");
 }

 // Create dummy bitmap.
 uint8_t rgbRaw[WIDTH * HEIGHT * 3];
 for (int row = 0; row < 32; row++)
 {
 for (int col = 0; col < 32; col++)
 {
 int index = row * WIDTH * 3 + col * 3;

 int red = (row < 16 && col < 16) ? 255 : 0;
 int green = (row < 16 && col > 16) ? 255 : 0;
 int blue = (row > 16 && col < 16) ? 255 : 0;

 rgbRaw[index] = (byte)red;
 rgbRaw[index + 1] = (byte)green;
 rgbRaw[index + 2] = (byte)blue;
 }
 }

 CreateBitmapFile(L"test-reference.bmp", WIDTH, HEIGHT, 24, rgbRaw, WIDTH * HEIGHT * 3);

 printf("Converting RGB to I420.\n");

 uint8_t* rgb[3];
 uint8_t* i420[3];
 int rgbStride[3], i420Stride[3];

 rgbStride[0] = w * 3;
 i420Stride[0] = w * h;
 i420Stride[1] = w * h / 4;
 i420Stride[2] = w * h / 4;

 rgb[0] = rgbRaw;
 i420[0] = (uint8_t*)malloc((size_t)i420Stride[0] * h);
 i420[1] = (uint8_t*)malloc((size_t)i420Stride[1] * h);
 i420[2] = (uint8_t*)malloc((size_t)i420Stride[2] * h);

 int toI420Res = sws_scale(rgbToI420Context, rgb, rgbStride, 0, h, i420, i420Stride);
 if (toI420Res < 0) {
 fprintf(stderr, "Conversion from RGB to I420 failed, %s.\n", av_make_error_string(_errorLog, ERROR_LEN, toI420Res));
 }

 printf("Converting I420 to RGB.\n");

 uint8_t* rgbOut[3];
 int rgbOutStride[3];

 rgbOutStride[0] = w * 3;
 rgbOut[0] = (uint8_t*)malloc((size_t)rgbOutStride[0] * h);

 int toRgbRes = sws_scale(i420ToRgbContext, i420, i420Stride, 0, h, rgbOut, rgbOutStride);
 if (toRgbRes < 0) {
 fprintf(stderr, "Conversion from RGB to I420 failed, %s.\n", av_make_error_string(_errorLog, ERROR_LEN, toRgbRes));
 }

 CreateBitmapFile(L"test-output.bmp", WIDTH, HEIGHT, 24, rgbOut, WIDTH * HEIGHT * 3);

 free(rgbOut[0]);

 for (int i = 0; i < 3; i++) {
 free(i420[i]);
 }

 sws_freeContext(rgbToI420Context);
 sws_freeContext(i420ToRgbContext);

 return 0;
}

/**
* Creates a bitmap file and writes to disk.
* @param[in] fileName: the path to save the file at.
* @param[in] width: the width of the bitmap.
* @param[in] height: the height of the bitmap.
* @param[in] bitsPerPixel: colour depth of the bitmap pixels (typically 24 or 32).
* @param[in] bitmapData: a pointer to the bytes containing the bitmap data.
* @param[in] bitmapDataLength: the number of pixels in the bitmap.
*/
void CreateBitmapFile(LPCWSTR fileName, long width, long height, WORD bitsPerPixel, BYTE* bitmapData, DWORD bitmapDataLength)
{
 HANDLE file;
 BITMAPFILEHEADER fileHeader;
 BITMAPINFOHEADER fileInfo;
 DWORD writePosn = 0;

 file = CreateFile(fileName, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL); //Sets up the new bmp to be written to

 fileHeader.bfType = 19778; //Sets our type to BM or bmp
 fileHeader.bfSize = sizeof(fileHeader.bfOffBits) + sizeof(RGBTRIPLE); //Sets the size equal to the size of the header struct
 fileHeader.bfReserved1 = 0; //sets the reserves to 0
 fileHeader.bfReserved2 = 0;
 fileHeader.bfOffBits = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER); //Sets offbits equal to the size of file and info header
 fileInfo.biSize = sizeof(BITMAPINFOHEADER);
 fileInfo.biWidth = width;
 fileInfo.biHeight = height;
 fileInfo.biPlanes = 1;
 fileInfo.biBitCount = bitsPerPixel;
 fileInfo.biCompression = BI_RGB;
 fileInfo.biSizeImage = width * height * (bitsPerPixel / 8);
 fileInfo.biXPelsPerMeter = 2400;
 fileInfo.biYPelsPerMeter = 2400;
 fileInfo.biClrImportant = 0;
 fileInfo.biClrUsed = 0;

 WriteFile(file, &fileHeader, sizeof(fileHeader), &writePosn, NULL);

 WriteFile(file, &fileInfo, sizeof(fileInfo), &writePosn, NULL);

 WriteFile(file, bitmapData, bitmapDataLength, &writePosn, NULL);

 CloseHandle(file);
}


The source bitmap is :




The output bmp after the two conversions is :




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Get blur effect inside a drawn box using ass format
18 septembre 2024, par Armen SanoyanI have
Nodejsapplication which generates subtitles file for video editing. The editing is done byffmpeg. For each word I also generate a backdrop with rounded corners using drawing command. Example of dialog for backdrop.

Dialogue: 0,00:00:38.60,00:00:42.10,Default,,0,0,0,,{\p1\1a&HD8&\c&HE27FA4&\pos(341.07421875,517.5)\an4} {\p1}m 15 0 b 1202.8515625 .... {\p0}


Now I want to make the backdrop blur.
(Text backdrop by ass formatting)


I have tried to use \blur or \be, but they are for other purpose. Below is reference from the doc


Enable or disable a subtle softening-effect for the edges of the text


Is there any other way to achieve the blurred backdrop. I am ready even to mix ffmpeg commands like
boxblurand ass file. I mean separately paint the backdrops and then apply ass subtitles file. Here is an experiment to explain the idea.

[0:v]split=3[base][blur1_in][blur2_in];

[blur1_in]crop=w=100:h=100:x=20:y=40[region1];
[region1]boxblur=luma_radius=10:luma_power=1[blurred_region1];
[base][blurred_region1]overlay=x=20:y=40:enable='between(t,0,5)'[tmp1];

[blur2_in]crop=w=30:h=30:x=20:y=40[region2];
[region2]boxblur=luma_radius=5:luma_power=1[blurred_region2];
[tmp1][blurred_region2]overlay=x=20:y=40:enable='between(t,5,10)'[tmp2];

[tmp2]ass=../logs/ass.ass:fontsdir=../fonts/Audiowide-Regular.ttf[final_video]


The problem in this case is that the corners are not rounded. Could anyone explain to me what is the easiest way to get backdrop with rounded corners an blurred inside


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how to apostrophe with os.system in ffmpeg drawtext in python
28 septembre 2023, par Ishu singhI just want to execute this code with os.system('command') in ffmpeg drawtext() but unable to execute it just because of ' (apostrophe) , it fails


The code goes here ->


the \f is working as \n but I'm using that for seprating word


from PIL import ImageFont
import os

def create_lines(longline, start, end, fontsize=75, fontfile='OpenSansCondensedBold.ttf'):

 fit = fit_text(longline, 700, fontfile)

 texts = []
 now = 0
 # breaking line on basis of '\f'
 for wordIndex in range(len(fit)):
 if fit[wordIndex] == '\f' or wordIndex == len(fit)-1:
 texts.append(fit[now:wordIndex+1].strip('\f'))
 now = wordIndex

 # adding multiple lines to video
 string = ''
 count = 0
 for line in texts:
 string += f''',drawtext=fontfile={fontfile}:fontsize={fontsize}:text='{line[enter image description here](https://i.stack.imgur.com/iuceq.png)}':fontcolor=black:bordercolor=white:borderw=4:x=(w-text_w)/2:y=(h-text_h)/2-100+{count}:'enable=between(t,{start},{end})' '''
 count += 100

 print(string)
 return string

def createVideo(content):
 input_video = 'video.mp4'
 output_video = 'output.mp4'
 font_file = 'BebasKai.ttf'
 text_file = 'OpenSansCondensedBold.ttf'
 font_size = 75
 font_color = 'white'

 part1 = create_lines(content[1], 0.5, 7)
 part2 = create_lines(content[2], 7.5, 10)

 os.system(
 f"""ffmpeg -i {} -vf "drawtext=fontfile={font_file}:fontsize={95}:text={content[0]}:fontcolor={font_color}:box=1:boxcolor=black@0.9:boxborderw=20:x=(w-text_w)/2:y=(h-text_h)/4-100{str(part1)}{str(part2)}" -c:v libx264 -c:a aac -t 10 {output_video} -y""")

my_text =['The Brain', "Your brain can't multitask effectively", "Multitasking is a myth, it's just rapid switching between tasks"]

createVideo(my_text)




what I want is that, I would able to execute this correctly


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