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Video d’abeille en portrait
14 mai 2011, par
Mis à jour : Février 2012
Langue : français
Type : Video
Autres articles (61)
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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 -
Encoding and processing into web-friendly formats
13 avril 2011, parMediaSPIP automatically converts uploaded files to internet-compatible formats.
Video files are encoded in MP4, Ogv and WebM (supported by HTML5) and MP4 (supported by Flash).
Audio files are encoded in MP3 and Ogg (supported by HTML5) and MP3 (supported by Flash).
Where possible, text is analyzed in order to retrieve the data needed for search engine detection, and then exported as a series of image files.
All uploaded files are stored online in their original format, so you can (...)
Sur d’autres sites (9206)
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How Funnel for Piwik Analytics enriches your Piwik experience giving you ultimate insights and debugging capabilities
13 janvier 2017, par InnoCraft — CommunityNo matter what type of website or app you have, whether you are trying to get your users to sign up for something or sell products, there is a certain number of steps your visitors have to go through. On every step you lose visitors and therefore potential revenue and conversions. Therefore it is critical to know where your visitors actually follow those steps in your website or app, where you lose them and where your visitors maybe get confused. By defining a funnel, you can improve your conversion rates, sales and revenue as you can exactly determine where you lose your visitors in converting your goal or a sale.
A Funnel defines a series of steps that you expect your visitors to take on their way to converting a goal. Funnels, a premium feature for Piwik developed by InnoCraft, lets you create funnels to get the data you need to improve your websites and mobile apps. Learn more about Funnel.
In this blog post we will cover the reports the Funnel plugin provides. The next blog post shows you how to configure and validate your funnel in Piwik.
Integration in Goal reports
At Piwik and InnoCraft, we usually start looking into our goal reports. Funnel integrates directly into each goal reporting page giving you a quick overview how your funnel is doing. This saves us a lot of time as we don’t have to separately look into each funnel page and only takes us maybe an additional second to keep an eye on our funnels. By clicking on the headline or “View funnel report” link, you can directly go to the funnel report to get a more detailed report if you notice any spike in the evolution of the conversions or conversion rate.
Getting an overall Funnel overview
Next we usually go to the “Funnel Overview” page where it shows a list of all activated Funnels and their performance over time. You will find the look familiar as it is similar to the “Goals Overview” page. If we find something unusual there, for example any spikes, we usually directly click on the headline of the Funnel to go to the detailed Funnel report. You can also choose a funnel from the left reporting menu or search for a funnel by entering the shortcut “f”.
Viewing a funnel report
A funnel reporting page looks very similar to a Goal reporting page. It starts with an evolution graph and sparklines showing you the performance of your funnel over time.
In the evolution graph you can select the metrics you want to plot. We usually have an eye on the funnel conversion rate and the number of “Funnel entries” or the number of “Funnel conversions”. The conversion rate alone does not show you how your funnel is performing. Imagine the rate is always stable at around 20% and you might think everything is alright, but if the number of visitors that take part in your funnel goes down, you might have a problem as the number of funnel conversions actually decreases even though the rate is the same. So we recommend to not only have a look at the conversion rate. The report will remember the metrics you want to plot each time you open it so you don’t have to re-select them over and over again.
The funnel overview
In the funnel overview we are giving you more details about the funnel and goal related conversion metrics so you don’t have to switch between the goal and funnel report and compare them easily.
When you analyze a funnel report, you might not always remember how the funnel is configured. Even though you specify names for each step you sometimes need to know on which pages a certain step will be activated. By clicking on the funnel summary link you can quickly look into the funnel configuration and also see all important metrics at a glance in a simple table without having to scroll.
You might also notice the Visitor Log link which will show you all actions for all visitors that have entered this funnel. This lets you really understand how your visitors navigate through your website and how they proceeded, exited or converted your funnel on a visitor level.
The Funnel visualization
Below the funnel overview you can visually see where your visitors entered, proceeded, converted and exited your funnel. We kept the UI clean so you can focus on the important things.
Most tools only give you the pages where visitors have entered your funnel but we do better and also show you the list of external referrers used by visitors to enter your funnel directly (marketing campaigns, search engines or other websites). Also we do not only show only the top 5 pages but up to 100 pages and 50 referrers (more can be configured if needed). When you hover a row, you will not only see the number of hits but also the percentage each row has contributed to the entries. Here you want to look and understand how your visitors enter your funnel and based on the data maybe invest in successful referrers, campaigns and pages. If the pages or referrers you expect to see there don’t show up, your users might not understand the path you had in mind for them.
Next you may notice how many visits have gone through each step, in this case 3487 visits. The green and red bar lets you quickly identify how many of your visitors have proceeded to the next step (green) compared to how many have exited the funnel at this step (red). Ideally, most of the bar is green and not red indicating that more visitors proceed to the next step than they exit.
Now the next feature is really valuable. When you hover the step title or the number of visits, you will notice that two icons appear :
Those two little icons are really powerful and give you even more insights to really dig into all the data. The left icon shows you the visitor log showing all actions of each visitor that have participated in this particular funnel step. This means for each step you get to see all the details and actions of each visitor. This lets you really debug and understand problems in your funnel.
At InnoCraft, we understand that plain numbers are often not so valuable. Only the evolution over time, when you put the numbers in relation to something else you can really understand how your website is doing. The icon to the right lets you do exactly this, it lets you view the row evolution for each funnel step. We are sure you will enjoy this feature. It lets you explore how each funnel step is doing over time. For example the number of entries for a step or how many proceeded to the next step from here over time. Here you ideally want to see that the “Proceeded Rate” increases over time, meaning more and more visitors actually proceed to the next step instead of exiting it.
We are sure you will really love those features that give you just those extra insights that other tools don’t give you.
On the right you can find out where your visitors went to, if they did not proceed any further in the funnel. This lets you better understand why they left the funnel and did not proceed any further.
At the end of the funnel report you find again the number of conversions and the conversion rate. Here we recommend looking into the visitor log when you hover the name of the last step as you can analyze how each visitor converted this funnel in detail.
Applying segments
Funnels lets you apply any Piwik segment to the Funnel report allowing you to dice your visitors multiplying the value you get out of Funnel. For example you may want to apply a segment and analyze the funnel for visitors that have visited your website or mobile app for the first time vs. recurring visitors. Sometimes it may be interesting how visitors from different countries go through your funnel, the possibilities are endless. We really recommend to take advantage of segments to understand your different target groups even better.
The plugin also adds some new segments to your Piwik letting you segment any Piwik report by visitors that have participated in a funnel or participated in a particular funnel step. For example you could go to the “Visitors => Locations” report and apply a segment for your funnel to see which countries have participated or converted most in your funnel.
Widgets, Scheduled Reports, and more.
This is not where the fun ends. Funnels defines new widgets that you can add to your dashboard or export it into a third party website. You can set up scheduled reports to receive the Funnel report automatically via email or sms or download the report to share it with your colleagues. It works also very well with Custom Alerts and you can view the Funnel report in the Piwik Mobile app. You can manage Funnels via HTTP API and also fetch all Funnel reports via the HTTP Reporting API. The plugin is really nicely integrated into Piwik we will need some more blog posts to show you all the ways Funnels advances your Piwik experience and how it lets you dig into all the data so you can increase your conversions and sales based on this data.
How to get Funnels and related features
You can get Funnels on the Piwik Marketplace. If you want to learn more about Funnels you might be also interested in the Funnel User Guide and the Funnel FAQ.
Similar to Funnels we also offer Users Flow which lets you visualize the flow of your users and visitors across several interactions.
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How to implement live video streaming with ffmpeg without using WebRTC ?
8 août 2024, par ArtemFollowing up on my previous question, I'd like to inquire about alternative methods for live video streaming using ffmpeg (WebRTC is not an option due to certain constraints I prefer not to discuss here).


Context :


I have a Go application where a goroutine launches ffmpeg to process a video stream, which is then delivered to the main goroutine via a
chan []byte
. I tried using WebSocket, but encountered issues as described in the previous question. HLS also didn't work well due to significant latency and artifacts like green squares on the video.

Based on a comment in the previous question, I attempted to stream the video via a simple GET request. Here's the Go handler I implemented :


func stream(helperApp agent.Helper) func(rw http.ResponseWriter, rr *http.Request) {
 a := atomic.Bool{}
 return func(rw http.ResponseWriter, rr *http.Request) {
 if !a.CAS(false, true) {
 http.Error(rw, "already running", http.StatusInternalServerError)
 return
 }

 rw.Header().Set("Access-Control-Allow-Origin", "*")
 rw.Header().Set("Content-Type", "video/mp2t")

 out := make(chan []byte)

 // create StreamParam
 go ScreenCaptureForLiveStream(StreamParam, out) // ffmpeg process starts inside

 r, w := io.Pipe()
 go func() {
 for data := range out {
 w.Write(data)
 fmt.Println(len(data))
 }
 }()
 io.Copy(rw, r)
 }
}




On the client side (HTML) :


<video muted="muted" src="http://localhost:8080/stream" controls="controls"></video>



In the browser console, I can see data being received, but the video doesn't play.


FFmpeg is executed with these parameters :


-loglevel error -f avfoundation -framerate 5 -capture_cursor 1 -capture_mouse_clicks 1 -i 1 -c:v libx264 -pix_fmt yuv420p -vf pad='ceil(iw/2)*2:ceil(ih/2)*2' -threads 0 -preset veryfast -bf 2 -f mpegts pipe:1




For validation, I ran :


ffmpeg -i http://localhost:8080/stream -c copy out.mp4




The video was successfully saved and plays.


Question :
What alternative methods exist to implement live video streaming with ffmpeg, aside from WebRTC ? Why does the current approach of streaming video via HTTP GET request not function correctly in the browser, and how can this be resolved ?


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FFmpeg concat video and audio out of sync
16 septembre 2016, par XeoncrossJoining multiple files using ffmpeg concat seems to result in a mismatch of the timestamps or offsets for the audio. I’ve tried with several videos and noticed the same problem for h.264 / MP4.
Using
concat
and encoding the video seems to work fine. The audio stays in sync as ffmpeg does the full conversion calculations and seems to get everything right.However, simply concatenating the videos without any transformation or encoding results in a slowly increasing sync issue. Obviously, encoding the videos rather than simply joining them will result in a loss of information/quality so I would rather find a way around this problem.
I’ve tried several flags to sort out this problem that appears to be based on the timestamps. None of these seem to correct the problem though.
ffmpeg -f concat -fflags +genpts -async 1 -i segments.txt test.mov
ffmpeg -auto_convert 1 -f concat -fflags +genpts -async 1 -i segments.txt -c copy test2.mov
ffmpeg -f concat -i segments.txt -c copy -fflags +genpts test3.mp4
ffmpeg -f concat -fflags +genpts -async 1 -i segments.txt -copyts test4.mov
ffmpeg -f concat -i segments.txt -copyts test5.mov
ffmpeg -f concat -i segments.txt -copyts -c copy test6.mov
ffmpeg -f concat -fflags +genpts -i segments.txt -copyts -c copy test7.movNote : all other questions that I could find on SO seem to "fix" the problem by simply encoding the videos over again. Not a good solution.
Update
I realized the concat wasn’t the problem. The original set of clips had mis-matched timestamps. Somehow concat + encoding fixed the issue, but I don’t want to re-encode the videos and loose quality each time.
ffmpeg -y -ss 00:00:02.750 -i input.MOV -c copy -t 00:00:05.880 output.MOV
Which resulted in the following data
ffprobe -v quiet -show_entries stream=start_time,duration output.MOV
start_time=-0.247500
duration=6.131125
start_time=-0.257333
duration=6.155333Since then I’ve tried to use
-to
m and-t
in different places along with-af apad -c:v copy
and I’ve still failed to get the duration to be the same.Here is the full ffprobe output
Here is the original (red) vs the segment (green)
Detailed Sample Files
I recorded a sample video, added the commands to chop it up, then concat it. http://davidpennington.me/share/audio_sync_test_video.zip