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Médias (1)
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The Great Big Beautiful Tomorrow
28 octobre 2011, par
Mis à jour : Octobre 2011
Langue : English
Type : Texte
Autres articles (53)
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Formulaire personnalisable
21 juin 2013, parCette page présente les champs disponibles dans le formulaire de publication d’un média et il indique les différents champs qu’on peut ajouter. Formulaire de création d’un Media
Dans le cas d’un document de type média, les champs proposés par défaut sont : Texte Activer/Désactiver le forum ( on peut désactiver l’invite au commentaire pour chaque article ) Licence Ajout/suppression d’auteurs Tags
On peut modifier ce formulaire dans la partie :
Administration > Configuration des masques de formulaire. (...) -
Amélioration de la version de base
13 septembre 2013Jolie sélection multiple
Le plugin Chosen permet d’améliorer l’ergonomie des champs de sélection multiple. Voir les deux images suivantes pour comparer.
Il suffit pour cela d’activer le plugin Chosen (Configuration générale du site > Gestion des plugins), puis de configurer le plugin (Les squelettes > Chosen) en activant l’utilisation de Chosen dans le site public et en spécifiant les éléments de formulaires à améliorer, par exemple select[multiple] pour les listes à sélection multiple (...) -
Qu’est ce qu’un masque de formulaire
13 juin 2013, parUn masque de formulaire consiste en la personnalisation du formulaire de mise en ligne des médias, rubriques, actualités, éditoriaux et liens vers des sites.
Chaque formulaire de publication d’objet peut donc être personnalisé.
Pour accéder à la personnalisation des champs de formulaires, il est nécessaire d’aller dans l’administration de votre MediaSPIP puis de sélectionner "Configuration des masques de formulaires".
Sélectionnez ensuite le formulaire à modifier en cliquant sur sont type d’objet. (...)
Sur d’autres sites (10913)
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Flutter : FFmpeg Not Executing Filter
5 novembre 2022, par Dennis AshfordI am downloading a video from Firebase and then trying to apply a watermark to that video that will then be saved in a temporary directory in the cache. I am using the
ffmpeg_kit_flutterpackage to do this. There is very little online about how this should work in Flutter.

The video and image are loaded and stored in the cache properly. However, the
FFmpegKit.executecall is not working and does not create a new output file in the cache. Any suggestions on how to make that function execute ? Are the FFmpeg commands correct ?

Future<string> waterMarkVideo(String videoPath, String watermarkPath) async {
 //these calls are to load the video into temporary directory
 final response = await http.get(Uri.parse(videoPath));
 final originalVideo = File ('${(await getTemporaryDirectory()).path}/video.mp4');
 await originalVideo.create(recursive: true);
 await originalVideo.writeAsBytes(response.bodyBytes);
 print('video path' + originalVideo.path);

 //this grabs the watermark image from assets and decodes it
 final byteData = await rootBundle.load(watermarkPath);
 final watermark = File('${(await getTemporaryDirectory()).path}/image.png');
 await watermark.create(recursive: true);
 await watermark.writeAsBytes(byteData.buffer.asUint8List(byteData.offsetInBytes, byteData.lengthInBytes));
 print('watermark path' + watermark.path);

 //this creates temporary directory for new watermarked video
 var tempDir = await getTemporaryDirectory();
 final newVideoPath = '${tempDir.path}/${DateTime.now().microsecondsSinceEpoch}result.mp4';

 //and now attempting to work with ffmpeg package to overlay watermark on video
 await FFmpegKit.execute("-i $originalVideo -i $watermark -filter_complex 'overlay[out]' -map '[out]' $newVideoPath")
 .then((rc) => print('FFmpeg process exited with rc $rc'));
 print('new video path' + newVideoPath);

return newVideoPath;
 }
</string>

The logs give the file paths and also give this


FFmpegKitFlutterPlugin 0x600000000fe0 started listening to events on 0x600001a4b280.
flutter: Loaded ffmpeg-kit-flutter-ios-https-x86_64-4.5.1.
flutter: FFmpeg process exited with rc Instance of 'FFmpegSession'


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Decompressing time-To-Sample table (STTS) in an MP4 file
30 mai 2016, par man-ri have an mp4 video byte array and i need to generate a thumbnail for it using its middle frame (e.g. if the video length is 10 seconds then i need to get the picture from 5th second).
i managed to parse through the file and extract its boxes (atom). i have also managed to get the video length from the mvhd box. also i managed to extract
1. the time-To-Sample table from stts box,
2. the sample-To-Chunk table from stcs box,
3. the chunk-Offset table from stco box,
4. the sample Size table from stsz box,
5. the Sync Sample table from stss boxi know that all the actual media are available in the mdat box and that i need to correlate the above table to find the exact frame offset in the file but my question is how ? the tables data seems to be compressed (specially the time-To-Sample table) but i don’t know how decompress them.
any help is appreciated.
below are code samples
code to convert byte to hex
public static char[] bytesToHex(byte[] bytes) {
char[] hexChars = new char[bytes.length * 2];
for ( int j = 0; j < bytes.length; j++ ) {
int v = bytes[j] & 0xFF;
hexChars[j * 2] = hexArray[v >>> 4];
hexChars[j * 2 + 1] = hexArray[v & 0x0F];
}
return hexChars;
}code for getting the box offset
final static String MOOV = "6D6F6F76";
final static String MOOV_MVHD = "6D766864";
final static String MOOV_TRAK = "7472616B";
final static String MOOV_TRAK_MDIA = "6D646961";
final static String MOOV_TRAK_MDIA_MINF = "6D696E66";
final static String MOOV_TRAK_MDIA_MINF_STBL = "7374626C";
final static String MOOV_TRAK_MDIA_MINF_STBL_STSD = "73747364";
final static String MOOV_TRAK_MDIA_MINF_STBL_STTS = "73747473";
final static String MOOV_TRAK_MDIA_MINF_STBL_STSS = "73747373";
final static String MOOV_TRAK_MDIA_MINF_STBL_STSC = "73747363";
final static String MOOV_TRAK_MDIA_MINF_STBL_STCO = "7374636F";
final static String MOOV_TRAK_MDIA_MINF_STBL_STSZ = "7374737A";
static int getBox(char[] s, int offset, String type) {
int typeOffset = -1;
for (int i = offset*2; i-1) {
break;
}
}
i+=(size*2);
}
return typeOffset;
}code for getting the duration and timescale
static int[] getDuration(char[] s) {
int mvhdOffset = getBox(s, 0, MOOV_MVHD);
int timeScaleStart = (mvhdOffset*2) + (4 + 4 + 1 + 3 + 4 + 4)*2;
int timeScaleEnd = (mvhdOffset*2) + (4 + 4 + 1 + 3 + 4 + 4 + 4)*2;
int durationStart = (mvhdOffset*2) + (4 + 4 + 1 + 3 + 4 + 4 + 4)*2;
int durationEnd = (mvhdOffset*2) + (4 + 4 + 1 + 3 + 4 + 4 + 4 + 4)*2;
String timeScaleHex = new String(Arrays.copyOfRange(s, timeScaleStart, timeScaleEnd));
String durationHex = new String(Arrays.copyOfRange(s, durationStart, durationEnd));
int timeScale = Integer.parseInt(timeScaleHex, 16);
int duration = Integer.parseInt(durationHex, 16);
int[] result = {duration, timeScale};
return result;
}code to get the time-To-Sample table
static int[][] getTimeToSampleTable(char[] s, int trakOffset) {
int offset = getBox(s, trakOffset, MOOV_TRAK_MDIA_MINF_STBL_STTS);
int sizeStart = offset*2;
int sizeEnd = offset*2 + (4)*2;
int typeStart = offset*2 + (4)*2;
int typeEnd = offset*2 + (4 + 4)*2;
int noOfEntriesStart = offset*2 + (4 + 4 + 1 + 3)*2;
int noOfEntriesEnd = offset*2 + (4 + 4 + 1 + 3 + 4)*2;
String sizeHex = new String(Arrays.copyOfRange(s, sizeStart, sizeEnd));
String typeHex = new String(Arrays.copyOfRange(s, typeStart, typeEnd));
String noOfEntriesHex = new String(Arrays.copyOfRange(s, noOfEntriesStart, noOfEntriesEnd));
int size = Integer.parseInt(sizeHex, 16);
int noOfEntries = Integer.parseInt(noOfEntriesHex, 16);
int[][] timeToSampleTable = new int[noOfEntries][2];
for (int i = 0; icode> -
MP4 file data structure
16 décembre 2015, par man-ri have an mp4 video byte array and i need to generate a thumbnail for it using its middle frame (e.g. if the video length is 10 seconds then i need to get the picture from 5th second).
i managed to parse through the file and extract its boxes (atom). i have also managed to get the video length from the mvhd box. also i managed to extract
1. the time-To-Sample table from stts box,
2. the sample-To-Chunk table from stcs box,
3. the chunk-Offset table from stco box,
4. the sample Size table from stsz box,
5. the Sync Sample table from stss boxi know that all the actual media are available in the mdat box and that i need to correlate the above table to find the exact frame offset in the file but my question is how ? the tables data seems to be compressed (specially the time-To-Sample table) but i don’t know how decompress them.
any help is appreciated.
below are code samples
code to convert byte to hex
public static char[] bytesToHex(byte[] bytes) {
char[] hexChars = new char[bytes.length * 2];
for ( int j = 0; j < bytes.length; j++ ) {
int v = bytes[j] & 0xFF;
hexChars[j * 2] = hexArray[v >>> 4];
hexChars[j * 2 + 1] = hexArray[v & 0x0F];
}
return hexChars;
}code for getting the box offset
final static String MOOV = "6D6F6F76";
final static String MOOV_MVHD = "6D766864";
final static String MOOV_TRAK = "7472616B";
final static String MOOV_TRAK_MDIA = "6D646961";
final static String MOOV_TRAK_MDIA_MINF = "6D696E66";
final static String MOOV_TRAK_MDIA_MINF_STBL = "7374626C";
final static String MOOV_TRAK_MDIA_MINF_STBL_STSD = "73747364";
final static String MOOV_TRAK_MDIA_MINF_STBL_STTS = "73747473";
final static String MOOV_TRAK_MDIA_MINF_STBL_STSS = "73747373";
final static String MOOV_TRAK_MDIA_MINF_STBL_STSC = "73747363";
final static String MOOV_TRAK_MDIA_MINF_STBL_STCO = "7374636F";
final static String MOOV_TRAK_MDIA_MINF_STBL_STSZ = "7374737A";
static int getBox(char[] s, int offset, String type) {
int typeOffset = -1;
for (int i = offset*2; i-1) {
break;
}
}
i+=(size*2);
}
return typeOffset;
}code for getting the duration and timescale
static int[] getDuration(char[] s) {
int mvhdOffset = getBox(s, 0, MOOV_MVHD);
int timeScaleStart = (mvhdOffset*2) + (4 + 4 + 1 + 3 + 4 + 4)*2;
int timeScaleEnd = (mvhdOffset*2) + (4 + 4 + 1 + 3 + 4 + 4 + 4)*2;
int durationStart = (mvhdOffset*2) + (4 + 4 + 1 + 3 + 4 + 4 + 4)*2;
int durationEnd = (mvhdOffset*2) + (4 + 4 + 1 + 3 + 4 + 4 + 4 + 4)*2;
String timeScaleHex = new String(Arrays.copyOfRange(s, timeScaleStart, timeScaleEnd));
String durationHex = new String(Arrays.copyOfRange(s, durationStart, durationEnd));
int timeScale = Integer.parseInt(timeScaleHex, 16);
int duration = Integer.parseInt(durationHex, 16);
int[] result = {duration, timeScale};
return result;
}code to get the time-To-Sample table
static int[][] getTimeToSampleTable(char[] s, int trakOffset) {
int offset = getBox(s, trakOffset, MOOV_TRAK_MDIA_MINF_STBL_STTS);
int sizeStart = offset*2;
int sizeEnd = offset*2 + (4)*2;
int typeStart = offset*2 + (4)*2;
int typeEnd = offset*2 + (4 + 4)*2;
int noOfEntriesStart = offset*2 + (4 + 4 + 1 + 3)*2;
int noOfEntriesEnd = offset*2 + (4 + 4 + 1 + 3 + 4)*2;
String sizeHex = new String(Arrays.copyOfRange(s, sizeStart, sizeEnd));
String typeHex = new String(Arrays.copyOfRange(s, typeStart, typeEnd));
String noOfEntriesHex = new String(Arrays.copyOfRange(s, noOfEntriesStart, noOfEntriesEnd));
int size = Integer.parseInt(sizeHex, 16);
int noOfEntries = Integer.parseInt(noOfEntriesHex, 16);
int[][] timeToSampleTable = new int[noOfEntries][2];
for (int i = 0; icode>
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