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Revolution of Open-source and film making towards open film making
6 octobre 2011, par
Mis à jour : Juillet 2013
Langue : English
Type : Texte
Autres articles (97)
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MediaSPIP 0.1 Beta version
25 avril 2011, parMediaSPIP 0.1 beta is the first version of MediaSPIP proclaimed as "usable".
The zip file provided here only contains the sources of MediaSPIP in its standalone version.
To get a working installation, you must manually install all-software dependencies on the server.
If you want to use this archive for an installation in "farm mode", you will also need to proceed to other manual (...) -
Multilang : améliorer l’interface pour les blocs multilingues
18 février 2011, parMultilang est un plugin supplémentaire qui n’est pas activé par défaut lors de l’initialisation de MediaSPIP.
Après son activation, une préconfiguration est mise en place automatiquement par MediaSPIP init permettant à la nouvelle fonctionnalité d’être automatiquement opérationnelle. Il n’est donc pas obligatoire de passer par une étape de configuration pour cela. -
HTML5 audio and video support
13 avril 2011, parMediaSPIP uses HTML5 video and audio tags to play multimedia files, taking advantage of the latest W3C innovations supported by modern browsers.
The MediaSPIP player used has been created specifically for MediaSPIP and can be easily adapted to fit in with a specific theme.
For older browsers the Flowplayer flash fallback is used.
MediaSPIP allows for media playback on major mobile platforms with the above (...)
Sur d’autres sites (5866)
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c++ avformat_open_input returns empty codec, width and height
27 février 2019, par Victor AkhlyninI haven’t ever used ffmpeg on my own laptop. All’s ok at work, but here I met an ugly problem : library works but helpless :)
Ubuntu 18.04, ffmpeg 4.1 (downloaded sources, ./configure, make, sudo make install), it seems to be ok.Application returns :
File /home/ahlininv/Desktop/video_example.mp4 is encodec with ’’ codec, w = 0, h = 0I ran it under debugger. If I set format to zero, pointer changes after calling avformat_open_input(&format, file, 0, &dict), so it works and maybe works correct.
Maybe it plays any role that compiler says that av_register_all, avcodec_register_all are deprecated, but I thought it’s not significant problem.
I tried to change version of ffmpeg (tried to install it with apt-get, version 3.somenumber is available), nothing changed.
I tried to run another video file (.avi), nothing changed, too.
Guys, help=) How to this file’s info correctly ?
main.cpp :
#include "filereader.h"
int main(int argc, char** argv) {
std::string filename = "/home/ahlininv/Desktop/video_example.mp4";
std::string codec;
int w, h;
bool open_ok = get_file_info(filename.c_str(), codec, w, h);
if (!open_ok) {
std::cout << "Failed to open file" << "\n";
return 1;
}
std::cout << "File " << filename << " is encoded with '" << codec << "' codec, w = " << w << ", h = " << h << "\n";
return 0;
}filereader.h :
#ifndef FILEREADER_H
#define FILEREADER_H
#include <string>
#include <iostream>
extern "C" {
#ifndef __STDC_CONSTANT_MACROS
#define __STDC_CONSTANT_MACROS
#endif
#include "libavcodec/avcodec.h"
#include <libavformat></libavformat>avformat.h>
#include <libavutil></libavutil>avutil.h>
}
bool get_file_info(const char* file, std::string& codec, int& w, int& h);
#endif // FILEREADER_H
</iostream></string>filereader.cpp
#include "filereader.h"
bool get_file_info(const char* file, std::string& codec, int& w, int& h)
{
codec = "";
w = h = 0;
av_register_all();
avcodec_register_all();
AVDictionary* dict = 0;
AVFormatContext* format = avformat_alloc_context();
char errbuf[256];
int r = avformat_open_input(&format, file, 0, &dict);
if (r!=0){
av_strerror(r, errbuf, sizeof(errbuf));
std::cout << "avformat_open_input error: " << errbuf << "\n";
}
if (r == AVERROR(EIO) || r == AVERROR(ENOEXEC) || !format)
return false;
for (size_t c = 0; c < format->nb_streams; ++c)
{
if (format->streams[c]->codecpar && format->streams[c]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO)
{
if (format->streams[c]->codecpar->codec_id != AV_CODEC_ID_NONE &&
format->streams[c]->codecpar->codec_id != AV_CODEC_ID_RAWVIDEO)
{
w = format->streams[c]->codecpar->width;
h = format->streams[c]->codecpar->height;
codec = avcodec_get_name(format->streams[c]->codecpar->codec_id);
}
}
}
avformat_close_input(&format);
return true;
}Compile :
g++ -o filereader main.cpp filereader.cpp -lavutil -lavformat -lavcodec -lavdevice -lz -lm -pthread -lswresample -lm -lz -I /usr/local/include/ -Wl,-rpath /usr/lib/x86_64-linux-gnu/
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FFMpeg avformat_write_header always returns 0
24 octobre 2015, par gabe.rozeWe’ve asked a freelancer to build a video encoder with FFMPeg for iOS but there is a bug and the freelancer is no longer available. I very inexperienced in FFMpeg and video encoding and am trying to debug this error.
From what I understand, we’re attempting to create an output file and create a header for it however, avformat_write_header is always less than zero. If I comment it out, it does not work
- (BOOL) writeHeaderWithError:(NSError *__autoreleasing *)error {
AVDictionary *options = NULL;
// Write header for output file
int writeHeaderValue = avformat_write_header(self.formatContext, &options);
if (writeHeaderValue < 0) {
if (error != NULL) {
*error = [FFUtilities errorForAVError:writeHeaderValue];
}
av_dict_free(&options);
return NO;
}
av_dict_free(&options);
return YES;
}Below is some relevant code of how we instantiate a FFOutputFile
- (AVFormatContext*) formatContextForOutputPath:(NSString*)outputPath options:(NSDictionary*)options {
AVFormatContext *outputFormatContext = NULL;
NSString *outputFormatString = [options objectForKey:kFFmpegOutputFormatKey];
int openOutputValue = avformat_alloc_output_context2(&outputFormatContext, NULL, [outputFormatString UTF8String], [outputPath UTF8String]);
if (openOutputValue < 0) {
avformat_free_context(outputFormatContext);
return nil;
}
return outputFormatContext;
}
- (void) addOutputStream:(FFOutputStream*)outputStream {
[self.streams addObject:outputStream];
}
- (id) initWithPath:(NSString *)path options:(NSDictionary *)options {
if (self = [super initWithPath:path options:options]) {
self.formatContext = [self formatContextForOutputPath:path options:options];
self.streams = [NSMutableArray array];
self.bitstreamFilters = [NSMutableSet set];
}
return self;
} -
FFMpeg avformat_write_header always returns < 0
7 mai 2024, par gabe.rozeWe've asked a freelancer to build a video encoder with FFMPeg for iOS but there is a bug and the freelancer is no longer available. I very inexperienced in FFMpeg and video encoding and am trying to debug this error.



From what I understand, we're attempting to create an output file and create a header for it however, avformat_write_header is always less than zero. If I comment it out, it does not work



- (BOOL) writeHeaderWithError:(NSError *__autoreleasing *)error {
 AVDictionary *options = NULL;

 // Write header for output file
 int writeHeaderValue = avformat_write_header(self.formatContext, &options);
 if (writeHeaderValue < 0) {
 if (error != NULL) {
 *error = [FFUtilities errorForAVError:writeHeaderValue];
 }
 av_dict_free(&options);
 return NO;
 }
 av_dict_free(&options);
 return YES;
}




Below is some relevant code of how we instantiate a FFOutputFile



- (AVFormatContext*) formatContextForOutputPath:(NSString*)outputPath options:(NSDictionary*)options {
 AVFormatContext *outputFormatContext = NULL;
 NSString *outputFormatString = [options objectForKey:kFFmpegOutputFormatKey];

 int openOutputValue = avformat_alloc_output_context2(&outputFormatContext, NULL, [outputFormatString UTF8String], [outputPath UTF8String]);
 if (openOutputValue < 0) {
 avformat_free_context(outputFormatContext);
 return nil;
 }
 return outputFormatContext;
}

- (void) addOutputStream:(FFOutputStream*)outputStream {
 [self.streams addObject:outputStream];
}

- (id) initWithPath:(NSString *)path options:(NSDictionary *)options {
 if (self = [super initWithPath:path options:options]) {
 self.formatContext = [self formatContextForOutputPath:path options:options];
 self.streams = [NSMutableArray array];
 self.bitstreamFilters = [NSMutableSet set];
 }
 return self;
}