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Le profil des utilisateurs
12 avril 2011, parChaque utilisateur dispose d’une page de profil lui permettant de modifier ses informations personnelle. Dans le menu de haut de page par défaut, un élément de menu est automatiquement créé à l’initialisation de MediaSPIP, visible uniquement si le visiteur est identifié sur le site.
L’utilisateur a accès à la modification de profil depuis sa page auteur, un lien dans la navigation "Modifier votre profil" est (...) -
Des sites réalisés avec MediaSPIP
2 mai 2011, parCette page présente quelques-uns des sites fonctionnant sous MediaSPIP.
Vous pouvez bien entendu ajouter le votre grâce au formulaire en bas de page. -
Configurer la prise en compte des langues
15 novembre 2010, parAccéder à la configuration et ajouter des langues prises en compte
Afin de configurer la prise en compte de nouvelles langues, il est nécessaire de se rendre dans la partie "Administrer" du site.
De là, dans le menu de navigation, vous pouvez accéder à une partie "Gestion des langues" permettant d’activer la prise en compte de nouvelles langues.
Chaque nouvelle langue ajoutée reste désactivable tant qu’aucun objet n’est créé dans cette langue. Dans ce cas, elle devient grisée dans la configuration et (...)
Sur d’autres sites (8544)
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arm : vp9itxfm : Skip empty slices in the first pass of idct_idct 16x16 and 32x32
9 janvier 2017, par Martin Storsjöarm : vp9itxfm : Skip empty slices in the first pass of idct_idct 16x16 and 32x32
This work is sponsored by, and copyright, Google.
Previously all subpartitions except the eob=1 (DC) case ran with
the same runtime :Cortex A7 A8 A9 A53
vp9_inv_dct_dct_16x16_sub16_add_neon : 3188.1 2435.4 2499.0 1969.0
vp9_inv_dct_dct_32x32_sub32_add_neon : 18531.7 16582.3 14207.6 12000.3By skipping individual 4x16 or 4x32 pixel slices in the first pass,
we reduce the runtime of these functions like this :vp9_inv_dct_dct_16x16_sub1_add_neon : 274.6 189.5 211.7 235.8
vp9_inv_dct_dct_16x16_sub2_add_neon : 2064.0 1534.8 1719.4 1248.7
vp9_inv_dct_dct_16x16_sub4_add_neon : 2135.0 1477.2 1736.3 1249.5
vp9_inv_dct_dct_16x16_sub8_add_neon : 2446.7 1828.7 1993.6 1494.7
vp9_inv_dct_dct_16x16_sub12_add_neon : 2832.4 2118.3 2266.5 1735.1
vp9_inv_dct_dct_16x16_sub16_add_neon : 3211.7 2475.3 2523.5 1983.1
vp9_inv_dct_dct_32x32_sub1_add_neon : 756.2 456.7 862.0 553.9
vp9_inv_dct_dct_32x32_sub2_add_neon : 10682.2 8190.4 8539.2 6762.5
vp9_inv_dct_dct_32x32_sub4_add_neon : 10813.5 8014.9 8518.3 6762.8
vp9_inv_dct_dct_32x32_sub8_add_neon : 11859.6 9313.0 9347.4 7514.5
vp9_inv_dct_dct_32x32_sub12_add_neon : 12946.6 10752.4 10192.2 8280.2
vp9_inv_dct_dct_32x32_sub16_add_neon : 14074.6 11946.5 11001.4 9008.6
vp9_inv_dct_dct_32x32_sub20_add_neon : 15269.9 13662.7 11816.1 9762.6
vp9_inv_dct_dct_32x32_sub24_add_neon : 16327.9 14940.1 12626.7 10516.0
vp9_inv_dct_dct_32x32_sub28_add_neon : 17462.7 15776.1 13446.2 11264.7
vp9_inv_dct_dct_32x32_sub32_add_neon : 18575.5 17157.0 14249.3 12015.1I.e. in general a very minor overhead for the full subpartition case due
to the additional loads and cmps, but a significant speedup for the cases
when we only need to process a small part of the actual input data.In common VP9 content in a few inspected clips, 70-90% of the non-dc-only
16x16 and 32x32 IDCTs only have nonzero coefficients in the upper left
8x8 or 16x16 subpartitions respectively.This is cherrypicked from libav commit
9c8bc74c2b40537b0997f646c87c008042d788c2.Signed-off-by : Michael Niedermayer <michael@niedermayer.cc>
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I cannot find any way to convert multiple jpg or png to gif in vb.net using ffmpeg
4 juillet 2017, par Silvia FonsecaIs there anyway i can get multiples png or jpg images to gif using ffmpeg in vb.net
I have start a new application to capture certain frames from a video but now i want to get all the frames extracted in gif image using ffmpeg.
This is my code so far :
I have in fact all ready try like this but not succeed
I have made some changes and i get the gif file but in empty state
This is my code so farImports System.Diagnostics
Imports System.ComponentModel
Imports System
Imports System.IO
Public Class Form1
Dim video = ""
Dim startInfo As New ProcessStartInfo("ffmpeg.exe")
Dim frame As Long 'individual frames
Dim tempdir As String = "C:\avitogifconverter\" ' images temp directory
Dim DestPath As String = "C:\avitogifconverter\"
Public Declare Auto Function FindWindowNullClassName Lib "user32.dll" Alias "FindWindow" (ByVal lpClassname As Integer, ByVal lpWindownName As String) As Integer
Dim Counter As Integer = 0
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
My.Computer.FileSystem.CreateDirectory(tempdir)
TextBox1.Text = "exp:-->video.avi or webm or flv"
TextBox1.Clear()
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim p As Process = Process.Start("cmd", "/k ffmpeg.exe -i " + TextBox1.Text + " -filter:v fps=1/15 C:\avitogifconverter\out%02d.jpg")
p.WaitForExit()
If p.HasExited Then
MsgBox("The Extraction Are Finish...")
End If
End Sub
Private Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Timer1.Tick
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
Label3.Text = "cmd" + "/k ffmpeg.exe -i " + TextBox1.Text + " -filter:v fps=1/15 C:\avi to gif converter\out%02d.jpg"
End Sub
Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
If (OpenFileDialog1.ShowDialog = Windows.Forms.DialogResult.OK) Then
'TextBox1.Text = OpenFileDialog1.FileName
TextBox1.Text = System.IO.Path.GetFileName(OpenFileDialog1.FileName)
End If
If TextBox1.Text = Nothing Then
Return
End If
If TextBox1.Text <> Nothing Then
'My.Computer.FileSystem.CopyFile(TextBox1.Text, DestPath)
End If
End Sub
Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
Dim args As String 'declare args
args = " -framerate 1/5 -i C:\avitogifconverter\out%02d.jpg -c:v libx264 -r 30 -pix_fmt yuv420p C:\avitogifconverter\out.gif "
Dim proc As New Process
Dim proci As New ProcessStartInfo
proci.FileName = My.Application.Info.DirectoryPath & "\ffmpeg.exe"
proci.Arguments = args
proci.WindowStyle = ProcessWindowStyle.Hidden
proci.CreateNoWindow = True
proci.UseShellExecute = False
proc.StartInfo = proci
proc.Start()
Do Until proc.HasExited = True
Me.Text = "Saving"
Loop
Me.Text = "your video done"
MsgBox("Done")
'IO.Directory.Delete(tempdir, True)
End Sub
End Class -
FFmpeg remuxing parts of an audio file
22 décembre 2022, par zorleoneI'm trying to remux individual tracks from a FLAC file using the FFmpeg libraries.
I get the starting timestamps from a Cue sheet, I seek to the timestamps using
avformat_seek_file. However after writing the packets to output files, they only have data from the beginning of the input file.

This is the code snippet which opens the input FLAC and also creates an output
AVFormatContextfor each track. I'm guessing the issue isavformat_seek_file, it doesn't seem to do anything, since even though I seek to the beginning of a track, the output file contains data from the beginning of the input.

for(int i = 0; i <= sheet.ntracks; i++) {
 sheet.avfmtctx = avformat_alloc_context();
 if(avformat_open_input(&sheet.avfmtctx, sheet.file, NULL, NULL) < 0) {
 fprintf(stderr,
 "avformat_open_input(): failed to open %s\n",
 sheet.file);
 return 1;
 }
 int audio_stream_idx = -1;
 for(int i = 0; i < sheet.avfmtctx->nb_streams; i++) {
 if(sheet.avfmtctx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
 audio_stream_idx = i;
 break;
 }
 }
 avformat_find_stream_info(sheet.avfmtctx, NULL);
 AVFormatContext *output;
 char *filepath = title_to_filepath(&sheet.tracks[i], sheet.file);
 avformat_alloc_output_context2(&output, NULL, NULL, filepath);
 AVStream *out_audio_stream = avformat_new_stream(output, NULL);
 avcodec_parameters_copy(out_audio_stream->codecpar,
 sheet.avfmtctx->streams[audio_stream_idx]->codecpar);

 if(avio_open(&output->pb, filepath, AVIO_FLAG_WRITE) < 0) {
 fprintf(stderr, "Failed to open %s for writing\n", filepath);
 return 1;
 }
 if(avformat_write_header(output, NULL) < 0) {
 fprintf(stderr, "avformat_write_header() failed\n");
 return 1;
 }
 int64_t current_frame = sheet.tracks[i].index;
 int64_t next_track_index = (i < sheet.ntracks) ?
 sheet.tracks[i + 1].index :
 INT64_MAX;
 if(avformat_seek_file(sheet.avfmtctx,
 -1,
 INT64_MIN,
 current_frame,
 current_frame,
 0) < 0) {
 fprintf(stderr, "Failed to seek to the index of track %d\n", i);
 avformat_free_context(sheet.avfmtctx);
 sheet.avfmtctx = NULL;
 av_write_trailer(output);
 avio_closep(&output->pb);
 avformat_free_context(output);
 free(filepath);
 continue;
 }
 AVPacket *pkt = av_packet_alloc();
 int64_t pts_diff = AV_NOPTS_VALUE, dts_diff = AV_NOPTS_VALUE;
 while(current_frame < next_track_index && !avio_feof(output->pb)) {
 int ret;
 if((ret = av_read_frame(sheet.avfmtctx, pkt)) < 0) {
 if(ret != AVERROR_EOF)
 fprintf(stderr, "av_read_frame() failed: %s\n", av_err2str(ret));
 break;
 }
 if(pkt->stream_index != audio_stream_idx)
 continue;
 // runs only once
 if(pts_diff == AV_NOPTS_VALUE && dts_diff == AV_NOPTS_VALUE) {
 pts_diff = pkt->pts;
 dts_diff = pkt->dts;
 }

 pkt->stream_index = 0; // first and only stream
 pkt->pts -= pts_diff;
 pkt->dts -= dts_diff;
 pkt->pos = -1;
 av_interleaved_write_frame(output, pkt);

 current_frame++;
 }

 avformat_free_context(sheet.avfmtctx);
 sheet.avfmtctx = NULL;

 av_write_trailer(output);
 av_packet_free(&pkt);
 avio_closep(&output->pb);
 avformat_free_context(output);

 free(filepath);
 }



current_frameandnext_track_indexare calculated from the INDEX lines in the Cue sheet :MM * 60 * 75 + SS * 75 + FF.
Can someone tell me what I'm doing wrong, and how to get the data I need from the input ?

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