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Médias (2)
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SPIP - plugins - embed code - Exemple
2 septembre 2013, par
Mis à jour : Septembre 2013
Langue : français
Type : Image
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Publier une image simplement
13 avril 2011, par ,
Mis à jour : Février 2012
Langue : français
Type : Video
Autres articles (53)
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Les autorisations surchargées par les plugins
27 avril 2010, parMediaspip core
autoriser_auteur_modifier() afin que les visiteurs soient capables de modifier leurs informations sur la page d’auteurs -
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 -
Support de tous types de médias
10 avril 2011Contrairement à beaucoup de logiciels et autres plate-formes modernes de partage de documents, MediaSPIP a l’ambition de gérer un maximum de formats de documents différents qu’ils soient de type : images (png, gif, jpg, bmp et autres...) ; audio (MP3, Ogg, Wav et autres...) ; vidéo (Avi, MP4, Ogv, mpg, mov, wmv et autres...) ; contenu textuel, code ou autres (open office, microsoft office (tableur, présentation), web (html, css), LaTeX, Google Earth) (...)
Sur d’autres sites (10509)
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Imagick and Gmagick builds available for Windows
The new Windows build page http://valokuva.org/magick/ contains builds for both Imagick and Gmagick. All builds are done using VC9 and PHP 5.3.
ImageMagick builds are QuantumDepth 16 (default).
GraphicsMagick builds are QuantumDepth 8 (default).Please note that these builds won’t work with the official PHP.net binaries which are compiled using VC6.
Edit : Pierre corrected me that there are official VC9 builds of PHP available at http://windows.php.net/download/
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Imagick and Gmagick builds available for Windows
The new Windows build page http://valokuva.org/magick/ contains builds for both Imagick and Gmagick. All builds are done using VC9 and PHP 5.3.
ImageMagick builds are QuantumDepth 16 (default).
GraphicsMagick builds are QuantumDepth 8 (default).Please note that these builds won’t work with the official PHP.net binaries which are compiled using VC6.
Edit : Pierre corrected me that there are official VC9 builds of PHP available at http://windows.php.net/download/
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What's the most desireable way to capture system display and audio in the form of individual encoded audio and video packets in go (language) ? [closed]
11 janvier 2023, par Tiger YangQuestion (read the context below first) :


For those of you familiar with the capabilities of go, Is there a better way to go about all this ? Since ffmpeg is so ubiquitous, I'm sure it's been optomized to perfection, but what's the best way to capture system display and audio in the form of individual encoded audio and video packets in go (language), so that they can be then sent via webtransport-go ? I wish for it to prioritize efficiency and low latency, and ideally capture and encode the framebuffer directly like ffmpeg does.


Thanks ! I have many other questions about this, but I think it's best to ask as I go.


Context and what I've done so far :


I'm writing a remote desktop software for my personal use because of grievances with current solutions out there. At the moment, it consists of a web app that uses the webtransport API to send input datagrams and receive AV packets on two dedicated unidirectional streams, and the webcodecs API to decode these packets. On the serverside, I originally planned to use python with the aioquic library as a webtransport server. Upon connection and authentication, the server would start ffmpeg as a subprocess with this command :


ffmpeg -init_hw_device d3d11va -filter_complex ddagrab=video_size=1920x1080:framerate=60 -vcodec hevc_nvenc -tune ll -preset p7 -spatial_aq 1 -temporal_aq 1 -forced-idr 1 -rc cbr -b:v 400K -no-scenecut 1 -g 216000 -f hevc -


What I really appreciate about this is that it uses windows' desktop duplication API to copy the framebuffer of my GPU and hand that directly to the on-die hardware encoder with zero round trips to the CPU. I think it's about as efficient and elegant a solution as I can manage. It then outputs the encoded stream to the stdout, which python can read and send to the client.


As for the audio, there is another ffmpeg instance :


ffmpeg -f dshow -channels 2 -sample_rate 48000 -sample_size 16 -audio_buffer_size 15 -i audio="RD Audio (High Definition Audio Device)" -acodec libopus -vbr on -application audio -mapping_family 0 -apply_phase_inv true -b:a 25K -fec false -packet_loss 0 -map 0 -f data -


which listens to a physical loopback interface, which is literally just a short wire bridging the front panel headphone and microphone jacks (I'm aware of the quality loss of converting to analog and back, but the audio is then crushed down to 25kbps so it's fine) ()


Unfortunately, aioquic was not easy to work with IMO, and I found webtransport-go https://github.com/adriancable/webtransport-go, which was a hell of a lot better in both simplicity and documentation. However, now I'm dealing with a whole new language, and I wanna ask : (above)


EDIT : Here's the code for my server so far :




package main

import (
 "bytes"
 "context"
 "fmt"
 "log"
 "net/http"
 "os/exec"
 "time"

 "github.com/adriancable/webtransport-go"
)

func warn(str string) {
 fmt.Printf("\n===== WARNING ===================================================================================================\n %s\n=================================================================================================================\n", str)
}

func main() {

 password := []byte("abc")

 videoString := []string{
 "ffmpeg",
 "-init_hw_device", "d3d11va",
 "-filter_complex", "ddagrab=video_size=1920x1080:framerate=60",
 "-vcodec", "hevc_nvenc",
 "-tune", "ll",
 "-preset", "p7",
 "-spatial_aq", "1",
 "-temporal_aq", "1",
 "-forced-idr", "1",
 "-rc", "cbr",
 "-b:v", "500K",
 "-no-scenecut", "1",
 "-g", "216000",
 "-f", "hevc", "-",
 }

 audioString := []string{
 "ffmpeg",
 "-f", "dshow",
 "-channels", "2",
 "-sample_rate", "48000",
 "-sample_size", "16",
 "-audio_buffer_size", "15",
 "-i", "audio=RD Audio (High Definition Audio Device)",
 "-acodec", "libopus",
 "-mapping_family", "0",
 "-b:a", "25K",
 "-map", "0",
 "-f", "data", "-",
 }

 connected := false

 http.HandleFunc("/", func(writer http.ResponseWriter, request *http.Request) {
 session := request.Body.(*webtransport.Session)

 session.AcceptSession()
 fmt.Println("\nAccepted incoming WebTransport connection.")
 fmt.Println("Awaiting authentication...")

 authData, err := session.ReceiveMessage(session.Context()) // Waits here till first datagram
 if err != nil { // if client closes connection before sending anything
 fmt.Println("\nConnection closed:", err)
 return
 }

 if len(authData) >= 2 && bytes.Equal(authData[2:], password) {
 if connected {
 session.CloseSession()
 warn("Client has authenticated, but a session is already taking place! Connection closed.")
 return
 } else {
 connected = true
 fmt.Println("Client has authenticated!\n")
 }
 } else {
 session.CloseSession()
 warn("Client has failed authentication! Connection closed. (" + string(authData[2:]) + ")")
 return
 }

 videoStream, _ := session.OpenUniStreamSync(session.Context())

 videoCmd := exec.Command(videoString[0], videoString[1:]...)
 go func() {
 videoOut, _ := videoCmd.StdoutPipe()
 videoCmd.Start()

 buffer := make([]byte, 15000)
 for {
 len, err := videoOut.Read(buffer)
 if err != nil {
 break
 }
 if len > 0 {
 videoStream.Write(buffer[:len])
 }
 }
 }()

 time.Sleep(50 * time.Millisecond)

 audioStream, err := session.OpenUniStreamSync(session.Context())

 audioCmd := exec.Command(audioString[0], audioString[1:]...)
 go func() {
 audioOut, _ := audioCmd.StdoutPipe()
 audioCmd.Start()

 buffer := make([]byte, 15000)
 for {
 len, err := audioOut.Read(buffer)
 if err != nil {
 break
 }
 if len > 0 {
 audioStream.Write(buffer[:len])
 }
 }
 }()

 for {
 data, err := session.ReceiveMessage(session.Context())
 if err != nil {
 videoCmd.Process.Kill()
 audioCmd.Process.Kill()

 connected = false

 fmt.Println("\nConnection closed:", err)
 break
 }

 if len(data) == 0 {

 } else if data[0] == byte(0) {
 fmt.Printf("Received mouse datagram: %s\n", data)
 }
 }

 })

 server := &webtransport.Server{
 ListenAddr: ":1024",
 TLSCert: webtransport.CertFile{Path: "SSL/fullchain.pem"},
 TLSKey: webtransport.CertFile{Path: "SSL/privkey.pem"},
 QuicConfig: &webtransport.QuicConfig{
 KeepAlive: false,
 MaxIdleTimeout: 3 * time.Second,
 },
 }

 fmt.Println("Launching WebTransport server at", server.ListenAddr)
 ctx, cancel := context.WithCancel(context.Background())
 if err := server.Run(ctx); err != nil {
 log.Fatal(err)
 cancel()
 }

}