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Personnaliser les catégories
21 juin 2013, parFormulaire de création d’une catégorie
Pour ceux qui connaissent bien SPIP, une catégorie peut être assimilée à une rubrique.
Dans le cas d’un document de type catégorie, les champs proposés par défaut sont : Texte
On peut modifier ce formulaire dans la partie :
Administration > Configuration des masques de formulaire.
Dans le cas d’un document de type média, les champs non affichés par défaut sont : Descriptif rapide
Par ailleurs, c’est dans cette partie configuration qu’on peut indiquer le (...) -
Les formats acceptés
28 janvier 2010, parLes commandes suivantes permettent d’avoir des informations sur les formats et codecs gérés par l’installation local de ffmpeg :
ffmpeg -codecs ffmpeg -formats
Les format videos acceptés en entrée
Cette liste est non exhaustive, elle met en exergue les principaux formats utilisés : h264 : H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 m4v : raw MPEG-4 video format flv : Flash Video (FLV) / Sorenson Spark / Sorenson H.263 Theora wmv :
Les formats vidéos de sortie possibles
Dans un premier temps on (...) -
Les vidéos
21 avril 2011, parComme les documents de type "audio", Mediaspip affiche dans la mesure du possible les vidéos grâce à la balise html5 .
Un des inconvénients de cette balise est qu’elle n’est pas reconnue correctement par certains navigateurs (Internet Explorer pour ne pas le nommer) et que chaque navigateur ne gère en natif que certains formats de vidéos.
Son avantage principal quant à lui est de bénéficier de la prise en charge native de vidéos dans les navigateur et donc de se passer de l’utilisation de Flash et (...)
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What is a Cohort Report ? A Beginner’s Guide to Cohort Analysis
3 janvier 2024, par ErinHandling your user data as a single mass of numbers is rarely conducive to figuring out meaningful patterns you can use to improve your marketing campaigns.
A cohort report (or cohort analysis) can help you quickly break down that larger audience into sequential segments and contrast and compare based on various metrics. As such, it is a great tool for unlocking more granular trends and insights — for example, identifying patterns in engagement and conversions based on the date users first interacted with your site.
In this guide, we explain the basics of the cohort report and the best way to set one up to get the most out of it.
What is a cohort report ?
In a cohort report, you divide a data set into groups based on certain criteria — typically a time-based cohort metric like first purchase date — and then analyse the data across those segments, looking for patterns.
Date-based cohort analysis is the most common approach, often creating cohorts based on the day a user completed a particular action — signed up, purchased something or visited your website. Depending on the metric you choose to measure (like return visits), the cohort report might look something like this :
Note that this is not a universal benchmark or anything of the sort. The above is a theoretical cohort analysis based on app users who downloaded the app, tracking and comparing the retention rates as the days go by.
The benchmarks will be drastically different depending on the metric you’re measuring and the basis for your cohorts. For example, if you’re measuring returning visitor rates among first-time visitors to your website, expect single-digit percentages even on the second day.
Your industry will also greatly affect what you consider positive in a cohort report. For example, if you’re a subscription SaaS, you’d expect high continued usage rates over the first week. If you sell office supplies to companies, much less so.
What is an example of a cohort ?
As we just mentioned, a typical cohort analysis separates users or customers by the date they first interacted with your business — in this case, they downloaded your app. Within that larger analysis, the users who downloaded it on May 3 represent a single cohort.
In this case, we’ve chosen behaviour and time — the app download day — to separate the user base into cohorts. That means every specific day denotes a specific cohort within the analysis.
Diving deeper into an individual cohort may be a good idea for important holidays or promotional events like Black Friday.
Of course, cohorts don’t have to be based on specific behaviour within certain periods. You can also create cohorts based on other dimensions :
- Transactional data — revenue per user
- Churn data — date of churn
- Behavioural cohort — based on actions taken on your website, app or e-commerce store, like the number of sessions per user or specific product pages visited
- Acquisition cohort — which channel referred the user or customer
For more information on different cohort types, read our in-depth guide on cohort analysis.
How to create a cohort report (and make sense of it)
Matomo makes it easy to view and analyse different cohorts (without the privacy and legal implications of using Google Analytics).
Here are a few different ways to set up a cohort report in Matomo, starting with our built-in cohorts report.
Cohort reports
With Matomo, cohort reports are automatically compiled based on the first visit date. The default metric is the percentage of returning visitors.
Changing the settings allows you to create multiple variations of cohort analysis reports.
Break down cohorts by different metrics
The percentage of returning visits can be valuable if you’re trying to improve early engagement in a SaaS app onboarding process. But it’s far from your only option.
You can also compare performance by conversion, revenue, bounce rate, actions per visit, average session duration or other metrics.
Change the time and scope of your cohort analysis
Splitting up cohorts by single days may be useless if you don’t have a high volume of users or visitors. If the average cohort size is only a few users, you won’t be able to identify reliable patterns.
Matomo lets you set any time period to create your cohort analysis report. Instead of the most recent days, you can create cohorts by week, month, year or custom date ranges.
Cohort sizes will depend on your customer base. Make sure each cohort is large enough to encapsulate all the customers in that cohort and not so small that you have insignificant cohorts of only a few customers. Choose a date range that gives you that without scaling it too far so you can’t identify any seasonal trends.
Cohort analysis can be a great tool if you’ve recently changed your marketing, product offering or onboarding. Set the data range to weekly and look for any impact in conversions and revenue after the changes.
Using the “compare to” feature, you can also do month-over-month, quarter-over-quarter or any custom date range comparisons. This approach can help you get a rough overview of your campaign’s long-term progress without doing any in-depth analysis.
You can also use the same approach to compare different holiday seasons against each other.
If you want to combine time cohorts with segmentation, you can run cohort reports for different subsets of visitors instead of all visitors. This can lead to actionable insights like adjusting weekend or specific seasonal promotions to improve conversion rates.
Try Matomo for Free
Get the web insights you need, without compromising data accuracy.
Easily create custom cohort reports beyond the time dimension
If you want to split your audience into cohorts by focusing on something other than time, you will need to create a custom report and choose another dimension. In Matomo, you can choose from a wide range of cohort metrics, including referrers, e-commerce signals like viewed product or product category, form submissions and more.
Then, you can create a simple table-based report with all the insights you need by choosing the metrics you want to see. For example, you could choose average visit duration, bounce rate and other usage metrics.
If you want more revenue-focused insights, add metrics like conversions, add-to-cart and other e-commerce events.
Custom reports make it easy to create cohort reports for almost any dimension. You can use any metric within demographic and behavioural analytics to create a cohort. (You can explore the complete list of our possible segmentation metrics.)
We cover different types of custom reports (and ideas for specific marketing campaigns) in our guide on custom segmentation.
Create your first cohort report and gain better insights into your visitors
Cohort reports can help you identify trends and the impact of short-term marketing efforts like events and promotions.
With Matomo cohort reports you have the power to create complex custom reports for various cohorts and segments.
If you’re looking for a powerful, easy-to-use web analytics solution that gives you 100% accurate data without compromising your users’ privacy, Matomo is a great fit. Get started with a 21-day free trial today. No credit card required.
Try Matomo for Free
21 day free trial. No credit card required.
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FFmpeg : How to create rotating 3D(haas) effect in mp3 using ffmpeg ?
30 octobre 2018, par AnkushI want to add a rotating 3d effect(Haas effect) in mp3. I mean that the audio will seem to change its directions from left to right and vice versa periodically(as shown below) when listened through the headphone. For this, I searched on the Internet and tried to achieve it in the following ways :
- Firstly, I thought, if I change the audio of the left and right channel periodically( Like when the Right channel has full volume(100%), Left channel has low volume(20%) and vice versa) then I can achieve it but it’s not like 3D.
- Secondly, When I researched more than found that It is done by creating a delay between the two channels. I found that I can create a delay of 0.0 to 0.8 milliseconds according to requirement.
To do this, I use the following commands in FFmpeg :
Step 1 : Splitting Audio Channels :
ffmpeg -i D:\ffmpeg\Down.mp3 -map_channel 0.0.0 D:\ffmpeg\L.mp3 -map_channel 0.0.1 D:\ffmpeg\R.mp3Stem 2 : Splitting Left channel into parts :
Note : We will only change the speed of Left channel so we split Left
channel into 4 seconds parts.ffmpeg -i D:\ffmpeg\L.mp3 -f segment -segment_time 4 D:\ffmpeg\Split\%03d.mp3Step 3 : Changing the tempo of each part
Now We change the tempo (speed) of each part so it may feel like the sound
is moving from left to right and vice versaffmpeg -y -i D:\ffmpeg\Split\000.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\000.mp3
ffmpeg -y -i D:\ffmpeg\Split\001.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\001.mp3
ffmpeg -y -i D:\ffmpeg\Split\002.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\002.mp3
ffmpeg -y -i D:\ffmpeg\Split\003.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\003.mp3
ffmpeg -y -i D:\ffmpeg\Split\004.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\004.mp3
ffmpeg -y -i D:\ffmpeg\Split\005.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\005.mp3
ffmpeg -y -i D:\ffmpeg\Split\006.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\006.mp3
ffmpeg -y -i D:\ffmpeg\Split\007.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\007.mp3
ffmpeg -y -i D:\ffmpeg\Split\008.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\008.mp3
ffmpeg -y -i D:\ffmpeg\Split\009.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\009.mp3
ffmpeg -y -i D:\ffmpeg\Split\010.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\010.mp3
ffmpeg -y -i D:\ffmpeg\Split\011.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\011.mp3
ffmpeg -y -i D:\ffmpeg\Split\012.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\012.mp3
ffmpeg -y -i D:\ffmpeg\Split\013.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\013.mp3
ffmpeg -y -i D:\ffmpeg\Split\014.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\014.mp3
ffmpeg -y -i D:\ffmpeg\Split\015.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\015.mp3
ffmpeg -y -i D:\ffmpeg\Split\016.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\016.mp3
ffmpeg -y -i D:\ffmpeg\Split\017.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\017.mp3
ffmpeg -y -i D:\ffmpeg\Split\018.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\018.mp3
ffmpeg -y -i D:\ffmpeg\Split\019.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\019.mp3
ffmpeg -y -i D:\ffmpeg\Split\020.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\020.mp3
ffmpeg -y -i D:\ffmpeg\Split\021.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\021.mp3
ffmpeg -y -i D:\ffmpeg\Split\022.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\022.mp3
ffmpeg -y -i D:\ffmpeg\Split\023.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\023.mp3
ffmpeg -y -i D:\ffmpeg\Split\024.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\024.mp3
ffmpeg -y -i D:\ffmpeg\Split\025.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\025.mp3
ffmpeg -y -i D:\ffmpeg\Split\026.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\026.mp3
ffmpeg -y -i D:\ffmpeg\Split\027.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\027.mp3
ffmpeg -y -i D:\ffmpeg\Split\028.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\028.mp3
ffmpeg -y -i D:\ffmpeg\Split\029.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\029.mp3
ffmpeg -y -i D:\ffmpeg\Split\030.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\030.mp3
ffmpeg -y -i D:\ffmpeg\Split\031.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\031.mp3
ffmpeg -y -i D:\ffmpeg\Split\032.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\032.mp3
ffmpeg -y -i D:\ffmpeg\Split\033.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\033.mp3
ffmpeg -y -i D:\ffmpeg\Split\034.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\034.mp3
ffmpeg -y -i D:\ffmpeg\Split\035.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\035.mp3
ffmpeg -y -i D:\ffmpeg\Split\036.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\036.mp3
ffmpeg -y -i D:\ffmpeg\Split\037.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\037.mp3
ffmpeg -y -i D:\ffmpeg\Split\038.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\038.mp3
ffmpeg -y -i D:\ffmpeg\Split\039.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\039.mp3
ffmpeg -y -i D:\ffmpeg\Split\040.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\040.mp3
ffmpeg -y -i D:\ffmpeg\Split\041.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\041.mp3
ffmpeg -y -i D:\ffmpeg\Split\042.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\042.mp3
ffmpeg -y -i D:\ffmpeg\Split\043.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\043.mp3
ffmpeg -y -i D:\ffmpeg\Split\044.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\044.mp3
ffmpeg -y -i D:\ffmpeg\Split\045.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\045.mp3
ffmpeg -y -i D:\ffmpeg\Split\046.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\046.mp3
ffmpeg -y -i D:\ffmpeg\Split\047.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\047.mp3
ffmpeg -y -i D:\ffmpeg\Split\048.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\048.mp3
ffmpeg -y -i D:\ffmpeg\Split\049.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\049.mp3
ffmpeg -y -i D:\ffmpeg\Split\050.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\050.mp3
ffmpeg -y -i D:\ffmpeg\Split\051.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\051.mp3
ffmpeg -y -i D:\ffmpeg\Split\052.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\052.mp3
ffmpeg -y -i D:\ffmpeg\Split\053.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\053.mp3
ffmpeg -y -i D:\ffmpeg\Split\054.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\054.mp3Here I used 1.0000 for normal speed
and 1.0008 for increased speed
and 0.9992 for decreased speedSpet 4 : Merging small pieces of audio
ffmpeg -f concat -safe 0 -i D:\ffmpeg\f.txt -c copy D:\ffmpeg\output.mp3where f.txt contains :
file 'D:\ffmpeg\Modi\000.mp3'
file 'D:\ffmpeg\Modi\001.mp3'
file 'D:\ffmpeg\Modi\002.mp3'
file 'D:\ffmpeg\Modi\003.mp3'
file 'D:\ffmpeg\Modi\004.mp3'
file 'D:\ffmpeg\Modi\005.mp3'
file 'D:\ffmpeg\Modi\006.mp3'
file 'D:\ffmpeg\Modi\007.mp3'
file 'D:\ffmpeg\Modi\008.mp3'
file 'D:\ffmpeg\Modi\009.mp3'
file 'D:\ffmpeg\Modi\010.mp3'
file 'D:\ffmpeg\Modi\011.mp3'
file 'D:\ffmpeg\Modi\012.mp3'
file 'D:\ffmpeg\Modi\013.mp3'
file 'D:\ffmpeg\Modi\014.mp3'
file 'D:\ffmpeg\Modi\015.mp3'
file 'D:\ffmpeg\Modi\016.mp3'
file 'D:\ffmpeg\Modi\017.mp3'
file 'D:\ffmpeg\Modi\018.mp3'
file 'D:\ffmpeg\Modi\019.mp3'
file 'D:\ffmpeg\Modi\020.mp3'
file 'D:\ffmpeg\Modi\021.mp3'
file 'D:\ffmpeg\Modi\022.mp3'
file 'D:\ffmpeg\Modi\023.mp3'
file 'D:\ffmpeg\Modi\024.mp3'Step 5 : The last operation is combining the both channels :
ffmpeg -i D:\ffmpeg\L.mp3 -i D:\ffmpeg\output.mp3 -filter_complex [0:a][1:a]amerge=inputs=2[aout] -map [aout] D:\ffmpeg\LRM.mp3But even then the result is very poor. It looks like FFmpeg combines audio in Step 4 took a delay after each audio.
I think there may be some bug in my solution. I don’t think that I can change tempo like this in audio without splitting the audio(Let me know if I am wrong).
Does anyone have a different solution to achieve this ?
Please help me in this. Thanks in advance... -
FFmpeg : How to create rotating 3D (haas) effect in mp3 using ffmpeg ?
7 février 2024, par ankushalgI want to add a rotating 3d effect (Haas effect) in mp3. I mean that the audio will seem to change its directions from left to right and vice versa periodically (as shown below) when listened through the headphone. For this, I searched on the Internet and tried to achieve it in the following ways :


- 

- Firstly, I thought, if I change the audio of the left and right channel periodically (like when the right channel has full volume (100%), left channel has low volume (20%) and vice versa) then I can achieve it, but it's not like 3D.
- Secondly, when I researched more than found that it is done by creating a delay between the two channels. I found that I can create a delay of 0.0 to 0.8 milliseconds according to requirement.
To do this, I use the following commands in FFmpeg :






Step 1 : Splitting Audio Channels :


ffmpeg -i D:\ffmpeg\Down.mp3 -map_channel 0.0.0 D:\ffmpeg\L.mp3 -map_channel 0.0.1 D:\ffmpeg\R.mp3


Stem 2 : Splitting Left channel into parts :




Note : We will only change the speed of Left channel so we split left
channel into 4 seconds parts.




ffmpeg -i D:\ffmpeg\L.mp3 -f segment -segment_time 4 D:\ffmpeg\Split\%03d.mp3


Step 3 : Changing the tempo of each part




Now We change the tempo (speed) of each part so it may feel like the sound
is moving from left to right and vice versa




ffmpeg -y -i D:\ffmpeg\Split\000.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\000.mp3
ffmpeg -y -i D:\ffmpeg\Split\001.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\001.mp3
ffmpeg -y -i D:\ffmpeg\Split\002.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\002.mp3
ffmpeg -y -i D:\ffmpeg\Split\003.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\003.mp3
ffmpeg -y -i D:\ffmpeg\Split\004.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\004.mp3
ffmpeg -y -i D:\ffmpeg\Split\005.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\005.mp3
ffmpeg -y -i D:\ffmpeg\Split\006.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\006.mp3
ffmpeg -y -i D:\ffmpeg\Split\007.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\007.mp3
ffmpeg -y -i D:\ffmpeg\Split\008.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\008.mp3
ffmpeg -y -i D:\ffmpeg\Split\009.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\009.mp3
ffmpeg -y -i D:\ffmpeg\Split\010.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\010.mp3
ffmpeg -y -i D:\ffmpeg\Split\011.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\011.mp3
ffmpeg -y -i D:\ffmpeg\Split\012.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\012.mp3
ffmpeg -y -i D:\ffmpeg\Split\013.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\013.mp3
ffmpeg -y -i D:\ffmpeg\Split\014.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\014.mp3
ffmpeg -y -i D:\ffmpeg\Split\015.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\015.mp3
ffmpeg -y -i D:\ffmpeg\Split\016.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\016.mp3
ffmpeg -y -i D:\ffmpeg\Split\017.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\017.mp3
ffmpeg -y -i D:\ffmpeg\Split\018.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\018.mp3
ffmpeg -y -i D:\ffmpeg\Split\019.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\019.mp3
ffmpeg -y -i D:\ffmpeg\Split\020.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\020.mp3
ffmpeg -y -i D:\ffmpeg\Split\021.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\021.mp3
ffmpeg -y -i D:\ffmpeg\Split\022.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\022.mp3
ffmpeg -y -i D:\ffmpeg\Split\023.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\023.mp3
ffmpeg -y -i D:\ffmpeg\Split\024.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\024.mp3
ffmpeg -y -i D:\ffmpeg\Split\025.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\025.mp3
ffmpeg -y -i D:\ffmpeg\Split\026.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\026.mp3
ffmpeg -y -i D:\ffmpeg\Split\027.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\027.mp3
ffmpeg -y -i D:\ffmpeg\Split\028.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\028.mp3
ffmpeg -y -i D:\ffmpeg\Split\029.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\029.mp3
ffmpeg -y -i D:\ffmpeg\Split\030.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\030.mp3
ffmpeg -y -i D:\ffmpeg\Split\031.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\031.mp3
ffmpeg -y -i D:\ffmpeg\Split\032.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\032.mp3
ffmpeg -y -i D:\ffmpeg\Split\033.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\033.mp3
ffmpeg -y -i D:\ffmpeg\Split\034.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\034.mp3
ffmpeg -y -i D:\ffmpeg\Split\035.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\035.mp3
ffmpeg -y -i D:\ffmpeg\Split\036.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\036.mp3
ffmpeg -y -i D:\ffmpeg\Split\037.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\037.mp3
ffmpeg -y -i D:\ffmpeg\Split\038.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\038.mp3
ffmpeg -y -i D:\ffmpeg\Split\039.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\039.mp3
ffmpeg -y -i D:\ffmpeg\Split\040.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\040.mp3
ffmpeg -y -i D:\ffmpeg\Split\041.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\041.mp3
ffmpeg -y -i D:\ffmpeg\Split\042.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\042.mp3
ffmpeg -y -i D:\ffmpeg\Split\043.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\043.mp3
ffmpeg -y -i D:\ffmpeg\Split\044.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\044.mp3
ffmpeg -y -i D:\ffmpeg\Split\045.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\045.mp3
ffmpeg -y -i D:\ffmpeg\Split\046.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\046.mp3
ffmpeg -y -i D:\ffmpeg\Split\047.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\047.mp3
ffmpeg -y -i D:\ffmpeg\Split\048.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\048.mp3
ffmpeg -y -i D:\ffmpeg\Split\049.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\049.mp3
ffmpeg -y -i D:\ffmpeg\Split\050.mp3 -af atempo=0.9992 D:\ffmpeg\Modi\050.mp3
ffmpeg -y -i D:\ffmpeg\Split\051.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\051.mp3
ffmpeg -y -i D:\ffmpeg\Split\052.mp3 -af atempo=1.0008 D:\ffmpeg\Modi\052.mp3
ffmpeg -y -i D:\ffmpeg\Split\053.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\053.mp3
ffmpeg -y -i D:\ffmpeg\Split\054.mp3 -af atempo=1.0000 D:\ffmpeg\Modi\054.mp3




Here I used 1.0000 for normal speed
and 1.0008 for increased speed
and 0.9992 for decreased speed




Spet 4 : Merging small pieces of audio


ffmpeg -f concat -safe 0 -i D:\ffmpeg\f.txt -c copy D:\ffmpeg\output.mp3


where f.txt contains :


file 'D:\ffmpeg\Modi\000.mp3'
file 'D:\ffmpeg\Modi\001.mp3'
file 'D:\ffmpeg\Modi\002.mp3'
file 'D:\ffmpeg\Modi\003.mp3'
file 'D:\ffmpeg\Modi\004.mp3'
file 'D:\ffmpeg\Modi\005.mp3'
file 'D:\ffmpeg\Modi\006.mp3'
file 'D:\ffmpeg\Modi\007.mp3'
file 'D:\ffmpeg\Modi\008.mp3'
file 'D:\ffmpeg\Modi\009.mp3'
file 'D:\ffmpeg\Modi\010.mp3'
file 'D:\ffmpeg\Modi\011.mp3'
file 'D:\ffmpeg\Modi\012.mp3'
file 'D:\ffmpeg\Modi\013.mp3'
file 'D:\ffmpeg\Modi\014.mp3'
file 'D:\ffmpeg\Modi\015.mp3'
file 'D:\ffmpeg\Modi\016.mp3'
file 'D:\ffmpeg\Modi\017.mp3'
file 'D:\ffmpeg\Modi\018.mp3'
file 'D:\ffmpeg\Modi\019.mp3'
file 'D:\ffmpeg\Modi\020.mp3'
file 'D:\ffmpeg\Modi\021.mp3'
file 'D:\ffmpeg\Modi\022.mp3'
file 'D:\ffmpeg\Modi\023.mp3'
file 'D:\ffmpeg\Modi\024.mp3'


Step 5 : The last operation is combining the both channels :


ffmpeg -i D:\ffmpeg\L.mp3 -i D:\ffmpeg\output.mp3 -filter_complex [0:a][1:a]amerge=inputs=2[aout] -map [aout] D:\ffmpeg\LRM.mp3


But even then the result is very poor. It looks like FFmpeg combines audio in Step 4 took a delay after each audio.


I think there may be some bug in my solution. I don't think that I can change tempo like this in audio without splitting the audio(Let me know if I am wrong).


Does anyone have a different solution to achieve this ?
Please help me in this. Thanks in advance...


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