Recherche avancée
Médias (2)
-
Valkaama DVD Label
4 octobre 2011, par
Mis à jour : Février 2013
Langue : English
Type : Image
-
Podcasting Legal guide
16 mai 2011, par
Mis à jour : Mai 2011
Langue : English
Type : Texte
Autres articles (52)
-
Use, discuss, criticize
13 avril 2011, parTalk to people directly involved in MediaSPIP’s development, or to people around you who could use MediaSPIP to share, enhance or develop their creative projects.
The bigger the community, the more MediaSPIP’s potential will be explored and the faster the software will evolve.
A discussion list is available for all exchanges between users. -
Selection of projects using MediaSPIP
2 mai 2011, parThe examples below are representative elements of MediaSPIP specific uses for specific projects.
MediaSPIP farm @ Infini
The non profit organizationInfini develops hospitality activities, internet access point, training, realizing innovative projects in the field of information and communication technologies and Communication, and hosting of websites. It plays a unique and prominent role in the Brest (France) area, at the national level, among the half-dozen such association. Its members (...) -
L’espace de configuration de MediaSPIP
29 novembre 2010, parL’espace de configuration de MediaSPIP est réservé aux administrateurs. Un lien de menu "administrer" est généralement affiché en haut de la page [1].
Il permet de configurer finement votre site.
La navigation de cet espace de configuration est divisé en trois parties : la configuration générale du site qui permet notamment de modifier : les informations principales concernant le site (...)
Sur d’autres sites (9260)
-
Getting Access Violations Exceptions in FFmpeg when trying to free IO buffer
26 juin 2015, par PatrikI’ve been trying to create an audio stream extractor/demuxer using FFmpeg.AutoGen and C#. While the code actually works (in the sense that it extracts the audio stream correctly), I can’t seem to clean up the resources afterwards. Whenever I try to free my input buffer (allocated using av_malloc) I get an Access Violation Exception, and if I don’t free it, I seem to be leaking memory corresponding to the size of the allocated input buffer.
This is my code (from a console application I used for testing) :
class Program
{
static void Main(string[] args)
{
using (var videoStream = Assembly.GetExecutingAssembly().GetManifestResourceStream("FFmpeg.Demux.test.mp4"))
using (MemoryStream output = new MemoryStream())
{
FFmpegAudioExtractor audioExtractor = new FFmpegAudioExtractor();
audioExtractor.Extract(videoStream, output);
Debug.Assert(1331200 == output.Length);
//File.WriteAllBytes(@"c:\temp\out.pcm", output.ToArray());
}
Console.WriteLine("Done");
Console.ReadLine();
}
}
public class FFmpegAudioExtractor
{
public FFmpegAudioExtractor()
{
FFmpegInvoke.av_register_all();
FFmpegInvoke.avcodec_register_all();
}
public unsafe void Extract(Stream input, Stream output)
{
AVFormatContext* inFormatContextPtr = null;
int inFomatContextOpenResult = -1;
byte* inIoBuffer = null;
AVIOContext* inIoContextPtr = null;
SwrContext* swrContextPtr = null;
AVFrame* inFramePtr = null;
AVFrame* outFramePtr = null;
AVCodecContext* inCodecContextPtr = null;
try
{
/* 1 */
inFormatContextPtr = FFmpegInvoke.avformat_alloc_context();
if (inFormatContextPtr == null)
throw new ApplicationException("Failed to allocate the input format context (AVFormatContext).");
// HACK this should alloc a fixed buffer and use callbacks to fill it
if (input.Length > int.MaxValue)
throw new ArgumentException("Data too large.", "input");
// TEST alloc a 10MB buffer to make the memory leak real obvious
int inIoBufferSize = 1024 * 1024 * 10; //(int)input.Length;
/* 2 */
inIoBuffer = (byte*)FFmpegInvoke.av_malloc((uint)inIoBufferSize);
if (inIoBuffer == null)
throw new ApplicationException("Failed to allocate the input IO buffer.");
// HACK continued, fill buffer
IntPtr inIoBufferPtr = new IntPtr(inIoBuffer);
byte[] buffer = new byte[4096];
int read, offset = 0;
while ((read = input.Read(buffer, 0, buffer.Length)) > 0)
{
Marshal.Copy(buffer, 0, inIoBufferPtr + offset, read);
offset += read;
}
/* 3 */
inIoContextPtr = FFmpegInvoke.avio_alloc_context((sbyte*)inIoBuffer,
inIoBufferSize,
0 /* writable */,
null,
IntPtr.Zero,
IntPtr.Zero,
IntPtr.Zero);
if (inIoContextPtr == null)
throw new ApplicationException("Failed to allocate the input IO context (AVIOContext).");
// configure the format context to use our custom IO contect
inFormatContextPtr->pb = inIoContextPtr;
inFormatContextPtr->flags = FFmpegInvoke.AVFMT_FLAG_CUSTOM_IO;
/* 35 */
inFomatContextOpenResult = FFmpegInvoke.avformat_open_input(&inFormatContextPtr, "", null, null);
if (inFomatContextOpenResult != 0)
throw new ApplicationException("Could not open input: " + inFomatContextOpenResult.ToString(CultureInfo.InvariantCulture));
// retrieve stream information
int avformatFindStreamInfoResult = FFmpegInvoke.avformat_find_stream_info(inFormatContextPtr, null);
if (avformatFindStreamInfoResult < 0)
throw new ApplicationException("Failed to locate stream info: " + avformatFindStreamInfoResult.ToString(CultureInfo.InvariantCulture));
// find audio stream
int inAudioStreamIndex = FFmpegInvoke.av_find_best_stream(inFormatContextPtr,
AVMediaType.AVMEDIA_TYPE_AUDIO,
-1 /* wanted_stream_nb */,
-1 /* related_stream */,
null /* [out] decoder */,
0 /* flags */);
if (inAudioStreamIndex < 0)
throw new ApplicationException("Failed to find audio stream: " + inAudioStreamIndex.ToString(CultureInfo.InvariantCulture));
// get audio stream pointer
AVStream* inAudioStreamPtr = inFormatContextPtr->streams[inAudioStreamIndex];
Contract.Assume(inAudioStreamPtr != null);
// find the decoder
AVCodec* inCodecPtr = FFmpegInvoke.avcodec_find_decoder(inAudioStreamPtr->codec->codec_id);
if (inCodecPtr == null)
throw new ApplicationException("Failed to find decoder with codec_id: " + inAudioStreamPtr->codec->codec_id.ToString());
/* 36 */
inCodecContextPtr = FFmpegInvoke.avcodec_alloc_context3(inCodecPtr);
if (FFmpegInvoke.avcodec_copy_context(inCodecContextPtr, inAudioStreamPtr->codec) != 0)
throw new ApplicationException("Failed to copy context.");
// open codec
/* 37 */
if (FFmpegInvoke.avcodec_open2(inCodecContextPtr, inCodecPtr, null) < 0)
{
string codecName = Marshal.PtrToStringAuto(new IntPtr(inCodecPtr->name));
throw new Exception("Failed to open codec: " + codecName);
}
// alloc frame
/* 38 */
inFramePtr = FFmpegInvoke.av_frame_alloc();
if (inFramePtr == null)
throw new ApplicationException("Could not allocate frame");
// initialize packet, set data to NULL, let the demuxer fill it
AVPacket packet = new AVPacket();
AVPacket* packetPtr = &packet;
FFmpegInvoke.av_init_packet(packetPtr);
packetPtr->data = null;
packetPtr->size = 0;
// alloc SWR
/* 4 */
swrContextPtr = FFmpegInvoke.swr_alloc();
AVSampleFormat outSampleFormat = AVSampleFormat.AV_SAMPLE_FMT_S16;
long outChannelLayout = FFmpegInvoke.AV_CH_FRONT_LEFT | FFmpegInvoke.AV_CH_FRONT_RIGHT;
// configure SWR
FFmpegInvoke.av_opt_set_sample_fmt(swrContextPtr, "in_sample_fmt", inCodecContextPtr->sample_fmt, 0);
FFmpegInvoke.av_opt_set_sample_fmt(swrContextPtr, "out_sample_fmt", outSampleFormat, 0);
// setting the in_channel_layout seems to break things
//FFmpegInvoke.av_opt_set_channel_layout(swrContextPtr, "in_channel_layout", (long)inCodecContextPtr->channel_layout, 0);
FFmpegInvoke.av_opt_set_channel_layout(swrContextPtr, "out_channel_layout", outChannelLayout, 0);
FFmpegInvoke.av_opt_set_int(swrContextPtr, "in_sample_rate", inCodecContextPtr->sample_rate, 0);
FFmpegInvoke.av_opt_set_int(swrContextPtr, "out_sample_rate", 44100, 0);
// allock output frane
/* 45 */
outFramePtr = FFmpegInvoke.av_frame_alloc();
outFramePtr->channel_layout = (ulong)outChannelLayout;
outFramePtr->sample_rate = 44100;
outFramePtr->format = (int)outSampleFormat;
// config done, init
FFmpegInvoke.swr_init(swrContextPtr);
bool frameFinished;
// read frames from the file
while (FFmpegInvoke.av_read_frame(inFormatContextPtr, packetPtr) >= 0)
{
AVPacket* origPacketPtr = packetPtr;
try
{
if (packetPtr->stream_index != inAudioStreamIndex)
continue;
do
{
byte[] decodedFrame;
int decodedBytes = this.DecodePacket(inCodecContextPtr,
packetPtr,
inFramePtr,
swrContextPtr,
outFramePtr,
out frameFinished,
out decodedFrame);
if (decodedBytes < 0)
break;
output.Write(decodedFrame, 0, decodedFrame.Length);
packetPtr->data += decodedBytes;
packetPtr->size -= decodedBytes;
} while (packetPtr->size > 0);
}
finally
{
FFmpegInvoke.av_free_packet(origPacketPtr);
}
}
// flush cached frames
packetPtr->data = null;
packetPtr->size = 0;
do
{
byte[] decodedFrame;
this.DecodePacket(inCodecContextPtr, packetPtr, inFramePtr, swrContextPtr, outFramePtr, out frameFinished, out decodedFrame);
if (decodedFrame != null)
output.Write(decodedFrame, 0, decodedFrame.Length);
} while (frameFinished);
}
finally
{
/* 45 */
if (outFramePtr != null)
FFmpegInvoke.av_frame_free(&outFramePtr);
/* 4 */
if (swrContextPtr != null)
FFmpegInvoke.swr_free(&swrContextPtr);
/* 38 */
if (inFramePtr != null)
FFmpegInvoke.av_frame_free(&inFramePtr);
/* 37 */
if (inCodecContextPtr != null)
FFmpegInvoke.avcodec_close(inCodecContextPtr);
/* 36 */
if (inCodecContextPtr != null)
FFmpegInvoke.avcodec_free_context(&inCodecContextPtr);
/* 35 */
if (inFomatContextOpenResult == 0)
FFmpegInvoke.avformat_close_input(&inFormatContextPtr);
/* 3 */
if (inIoContextPtr != null)
FFmpegInvoke.av_freep(&inIoContextPtr);
//* 2 */
if (inIoBuffer != null)
FFmpegInvoke.av_freep(&inIoBuffer);
/* 1 */
// This is called by avformat_close_input
if (inFormatContextPtr != null)
FFmpegInvoke.avformat_free_context(inFormatContextPtr);
}
}
private unsafe int DecodePacket(AVCodecContext* audioDecoderContextPtr, AVPacket* packetPtr, AVFrame* inFramePtr, SwrContext* swrContextPtr, AVFrame* outFramePtr, out bool frameDecoded, out byte[] decodedFrame)
{
decodedFrame = null;
/* decode audio frame */
int gotFrame;
int readBytes = FFmpegInvoke.avcodec_decode_audio4(audioDecoderContextPtr, inFramePtr, &gotFrame, packetPtr);
if (readBytes < 0)
throw new ApplicationException("Error decoding audio frame: " + readBytes.ToString(CultureInfo.InvariantCulture));
frameDecoded = gotFrame != 0;
/* Some audio decoders decode only part of the packet, and have to be
* called again with the remainder of the packet data.
* Sample: fate-suite/lossless-audio/luckynight-partial.shn
* Also, some decoders might over-read the packet. */
int decoded = Math.Min(readBytes, packetPtr->size);
if (frameDecoded)
{
if (FFmpegInvoke.swr_convert_frame(swrContextPtr, outFramePtr, inFramePtr) != 0)
throw new ApplicationException("Failed to convert frame.");
long delay;
do
{
int unpaddedLinesize = outFramePtr->nb_samples * outFramePtr->channels * FFmpegInvoke.av_get_bytes_per_sample((AVSampleFormat)outFramePtr->format);
IntPtr dataPtr = new IntPtr(outFramePtr->extended_data[0]);
decodedFrame = new byte[unpaddedLinesize];
Marshal.Copy(dataPtr, decodedFrame, 0, unpaddedLinesize);
// check if we have more samples to convert for this frame
delay = FFmpegInvoke.swr_get_delay(swrContextPtr, 44100);
if (delay > 0)
{
if (FFmpegInvoke.swr_convert_frame(swrContextPtr, outFramePtr, null) != 0)
throw new ApplicationException("Failed to convert frame.");
}
} while (delay > 0);
}
return decoded;
}
}The failing line is :
FFmpegInvoke.av_freep(&inIoBuffer); -
How can I transcode a file with FFMPEG and stream the output file in the response of a Java servlet ?
6 octobre 2012, par user1700589Basically, this is what I'm trying to do :
1. User passes a URL as a GET parameter to my servlet.
2. Servlet uses a ProcessBuilder to convert the media contained in that URL to a valid media format (ie : MP3).
3. The servlet streams the output file being transcoded by FFMPEG back to the browser.1 and 2 work fine, but it is 3 I am having a problem with. The best I can do is create a FileInputStream to the output file being transcoded and send that as the response but it is not working. My guess is that it is because the file is being written as I'm trying to stream it.
Is there anyway to intercept the output file argument in FFMPEG and read it into an InputStream ? In my mind it does not seem that it should be difficult to take input file A, transcode it to output file B, and then stream output file B back to the client, on the fly.
ProcessBuilder pb = new ProcessBuilder("ffmpeg.exe", "-i", url, "file.mp3");
Process p = pb.start();
final InputStream inStream = p.getErrorStream();
new Thread(new Runnable() {
public void run() {
InputStreamReader reader = new InputStreamReader(inStream);
Scanner scan = new Scanner(reader);
while (scan.hasNextLine()) {
System.out.println(scan.nextLine());
}
}
}).start();
ServletOutputStream stream = null;
BufferedInputStream buf = null;
try {
stream = response.getOutputStream();
File mp3 = new File(file.mp3");
//set response headers
response.setContentType("audio/mpeg");
response.addHeader("Content-Disposition", "attachment; filename=file.mp3");
response.setContentLength(-1);
//response.setContentLength((int) mp3.length());
FileInputStream input = new FileInputStream(mp3);
buf = new BufferedInputStream(input);
int readBytes = 0;
//read from the file; write to the ServletOutputStream
while ((readBytes = buf.read()) != -1) {
stream.write(readBytes);
}
} catch (IOException ioe) {
throw new ServletException(ioe.getMessage());
} finally {
if (stream != null) {
stream.close();
}
if (buf != null) {
buf.close();
}
} -
FFMPEG with PHP does not execute ?
15 septembre 2012, par ConorAfter reading about a gazillion questions here on SO related to FFMPEG with PHP I have gotten together a small snippet or what-not, but it does not seem to do anything - not even throw errors.
My PHP is as follows :
function get_video_thumbnail($file) {
define('ALL_PLACE_WIDTH', 250);
define('ALL_PLACE_HEIGHT', 200);
$ffmpeg = "ffmpeg"; // where ffmpeg is
$image_source_path = $file; // where the video is
$image_cmd = " -r 1 -ss 00:00:10 -t 00:00:01 -s ".ALL_PLACE_WIDTH."x".ALL_PLACE_HEIGHT." -f image2 "; // command
$dest_image_path = "cdn/thumbnails"; // destination of thumbnail
$str_command = $ffmpeg ." -i " . $image_source_path . $image_cmd .$dest_image_path;
shell_exec($str_command);
}in the root folder there's a folder "ffmpeg" in what there's "ffmpeg.exe", "ffplay.exe" and "pthreadGC2.dll". So I'm wondering, is there anything I'm missing ? I'm trying to generate a thumbnail from a video/mp4 file.
Syndiquer tout le site
