Applications

How to speed up Youtube videos more than 2x

 in Applications  tagged browser / console / speed / youtube by

Using the playbackRate command to adjust video playback speed on YouTube slightly differs from using it on a standard HTML video element. This is because YouTube uses its player interface, built on top of the HTML5 video API but includes additional features and customizations.

Here’s a step-by-step guide on how to use the playbackRate command on YouTube:

Open YouTube and Select a Video: Navigate to YouTube and open the video you want to adjust.

Access the Browser Console:

  • Open Developer Tools in your browser. This is usually done by right-clicking on the page and selecting “Inspect,” or by pressing Ctrl+Shift+I (Windows/Linux) or Cmd+Option+I (Mac).
  • Switch to the “Console” tab.

Use the Correct JavaScript Command:

  • On YouTube, the video player element can be accessed differently. The command to adjust the playback speed might look like this:
  • document.querySelector('video').playbackRate = X;
  • Replace X with the desired playback speed. For example, 1.5 for 1.5x speed, or 0.75 for 75% of the normal speed.
document.querySelector('video').playbackRate = X;

For regular use, the built-in speed settings in the YouTube player (accessible via the gear icon in the player controls) are the recommended and easiest method to change playback speed. They provide a range of speed options in a user-friendly manner without the need for coding or console commands.

Understanding the playbackRate Command in JavaScript

document.getElementsByTagName("video")[0].playbackRate = X;

In the dynamic world of web development, JavaScript stands as a cornerstone technology, enabling developers and users to interact with web content in powerful ways. Among its many features is the ability to control video playback on web pages. This blog post delves into one such aspect: using the playbackRate command to control the speed of video playback.

What is playbackRate?

The playbackRate property in JavaScript is a feature of the HTML5 Video API. It allows developers to change the speed at which a video plays on a web page. The command document.getElementsByTagName("video")[0].playbackRate = X; is a practical implementation of this feature.

Breaking Down the Command

  • document: This is the root node of the HTML document.
  • getElementsByTagName("video"): This method returns a live HTMLCollection of elements with the specified tag name, in this case, “video”.
  • [0]: Since getElementsByTagName returns a collection, [0] accesses the first video element in the collection. If there are multiple videos, changing the index accesses different videos.
  • playbackRate: This property sets or returns the current playback speed of the video. 1 is the normal speed, values greater than 1 increase the speed, and values between 0 and 1 slow it down.
  • X: This represents the desired playback speed. For instance, setting X to 1.5 would make the video play at 1.5 times its normal speed.

Practical Use Cases

  • Educational Content: Speed up or slow down instructional videos to match the learner’s pace.
  • Accessibility: Adjust video speed for viewers who need more time to process visual content.
  • Entertainment: Speed through slow sections of videos or slow down for detailed analysis of scenes.

How to Implement

  1. Identify the Video: Ensure the video element is correctly targeted, especially in pages with multiple videos.
  2. Set the Playback Speed: Assign the desired speed to playbackRate. For example, document.getElementsByTagName("video")[0].playbackRate = 1.5; speeds up the first video by 50%.
  3. Test and Debug: Verify that the speed adjustment works across different browsers and devices.

Best Practices

  • User Control: Ideally, provide a user interface for viewers to adjust the speed according to their preference.
  • Browser Compatibility: Test the functionality in various browsers to ensure consistent behavior.
  • Fallbacks: In cases where playbackRate is not supported, consider alternative methods or inform the user.

Conclusion

The playbackRate property in JavaScript offers a simple yet powerful tool for enhancing the video viewing experience on web pages. By understanding and utilizing this command, developers can provide more dynamic and user-friendly web applications. Whether it’s for educational purposes, accessibility, or just personal preference, the ability to control video playback speed is an invaluable feature in today’s web landscape.

Understanding the cURL Command for Performance Metrics

 in Applications / GNU/Linux  tagged curl by

Breaking Down the Command

In the world of web development and network administration, the cURL command is a versatile tool used for transferring data using various protocols. One interesting application of this command is to measure the performance of a web server. Let’s dissect a specific cURL command to understand how it works:

curl -svo /dev/null -w "Connect: %{time_connect} \n TTFB: %{time_starttransfer} \n Total time: %{time_total} \n" https://bytefreaks.net/;

Components of the Command

  1. curl: This is the basic command call for using cURL, which initiates the data transfer.
  2. -sv: The -s flag stands for ‘silent’, which makes cURL less talkative by hiding the progress meter and error messages. The -v flag is for ‘verbose’, providing more information about the transaction. These flags might seem contradictory, but together, they suppress unnecessary details while keeping the essential info visible.
  3. /dev/null: This part redirects the output of the command to a special file that discards all data written to it. In essence, it’s used here to ignore the body of the response.
  4. -w: This flag is used to specify what data to display on the screen after the execution of the command. It stands for ‘write-out’.
  5. "Connect: %{time_connect} \n TTFB: %{time_starttransfer} \n Total time: %{time_total} \n": This is a formatted string that curl will use to display the timing statistics:
    • %{time_connect}: Shows the time it took to establish the connection to the server.
    • %{time_starttransfer}: Stands for ‘Time to First Byte’ (TTFB), indicating the time from the start until the first byte is received.
    • %{time_total}: Displays the total time taken for the operation.
  6. https://bytefreaks.net/: This is the URL to which the cURL request is made.

Practical Use

This command is particularly useful for testing the performance of web servers. By analyzing the connect time, TTFB, and total time, administrators and developers can get insights into potential bottlenecks or performance issues. For instance, a long TTFB might suggest server-side delays in processing requests.

Conclusion

The cURL command demonstrated here is a powerful tool for performance testing. It’s concise yet provides crucial metrics for understanding how a web server responds to requests. By mastering such commands, one can effectively monitor and optimize web server performance, ensuring better user experiences and efficient server management.

Beware of Phishing Links on Viber: A Security Alert

 in Applications  tagged phishing / scam / security / viber by

In the age of instant communication, apps like Viber have become integral to our daily interactions. However, with the convenience of quick chats and video calls comes the risk of cyber threats. A recent security concern involves phishing links circulating on Viber, particularly those starting with “https://www.viber.com/activate_secondary/“. If you encounter such a link, exercise caution: clicking on it may compromise your account.

What Is a Phishing Link?

Phishing links are malicious URLs designed to steal personal information. Hackers craft these links to look legitimate, tricking users into handing over sensitive details like login credentials. Once clicked, these links can lead to unauthorized access to your accounts, financial loss, or identity theft.

The Viber Scam: What You Need to Know

On Viber, the scam link in question is part of a ploy to hack into accounts. The link prompts users to “activate” a secondary device, but in reality, it’s a method for a hacker to log in to your Viber account using their PC. The link is a disguised trap, and the consequences of clicking it are serious. The hacker can gain full access to your Viber account, allowing them to read your messages, access your contact list, and impersonate you.

How to Remove the access of a Hacker to your account

To deactivate Viber on your Desktop and Tablets from your mobile phone, you should follow these steps:

  1. Open the Viber app on your mobile device.
  2. Tap on More or the three lines in the bottom right corner to access the menu.
  3. Select Settings to open the settings menu.
  4. Go to the Account section.
  5. Tap on Desktop and Tablets. This will show a list of devices where your Viber account is active.
  6. From the list, select the device you want to deactivate.
  7. Confirm the deactivation when prompted.

This process will remove your Viber account from the selected devices, ensuring that no one can use it on those devices unless you activate them again​.

How to Protect Yourself

  • Don’t Click Suspicious Links: If you receive a link you weren’t expecting or that looks out of the ordinary, do not click on it.
  • Verify the Source: If a contact sends you a link, verify with them through a different communication method to confirm they intended to send it.
  • Use Official Channels: Always use the official Viber website or app for account-related actions.
  • Stay Informed: Keep up with the latest security updates from Viber and be aware of common phishing tactics.

Conclusion

Your digital safety is paramount. In the face of cunning cyber-attacks, staying informed and vigilant is your best defense. Remember, if you receive any link starting with “https://www.viber.com/activate_secondary/“, do not click on it. Protect yourself and your digital presence by being cautious and proactive about your online security.

Stay safe, stay connected.

Some technical information

As you will see in the following example, the link translates to a Viber command that prompts the device to accept the attacker’s device as a legitimate user device.

wget 'https://www.viber.com/activate_secondary/?u=bf63cd32389dcc342088c477a&k=u54BFqCQKGrL5-xPhV_Px82.&r=1&v=2'
--2023-11-02 16:21:36--  https://www.viber.com/activate_secondary/?u=bf63cd32389dcc342088c477a&k=u54BFqCQKGrL5-xPhV_Px82.&r=1&v=2
Resolving www.viber.com (www.viber.com)... 104.103.81.52, 2a02:26f0:9c00:395::24c5, 2a02:26f0:9c00:396::24c5
Connecting to www.viber.com (www.viber.com)|104.103.81.52|:443... connected.
HTTP request sent, awaiting response... 302 Moved Temporarily
Location: viber://auth?u=bf63cd32389dcc342088c477a&k=u54BFqCQKGrL5-xPhV_Px82.&r=1&v=2 [following]
viber://auth?u=bf63cd32389dcc342088c477a&k=u54BFqCQKGrL5-xPhV_Px82.&r=1&v=2: Unsupported scheme ‘viber’.

How to “group by” and sum or count in LibreOffice Calc (Excel)

 in Applications  tagged calc / excel / group by / LibreOffice / Subtotal by

In the world of spreadsheet applications, LibreOffice Calc stands out as a versatile and powerful tool for managing data. It offers a wide array of features that can help you organize, analyze, and make sense of your data. One of these features, often underutilized, is the Subtotals functionality. In this blog post, we’ll explore how to use the Subtotals functionality in the Data menu of LibreOffice Calc to count how many times each item is repeated in a dataset. This is particularly useful when working with large datasets or lists, as it allows you to create summary reports without the need for complex formulas or manual counting.

Preparing Your Data

Start by opening LibreOffice Calc and loading the dataset you want to analyze. Ensure that your data is organized in columns and that each item you want to count is in a separate column. For example, if you have a list of products, each product name should be in its own column.

Sorting Your Data

To use the Subtotals functionality effectively, your data needs to be sorted by the column containing the items you want to count. To sort your data:

  • Select the entire dataset by clicking and dragging your mouse.
  • Go to the “Data” menu, and then click on “Sort.”

Sort Data

  • In the “Sort Criteria” dialog box, select the column containing the items you want to count.
  • Choose the sorting order (ascending or descending), and click “OK.”

Your data is now sorted and ready for subtotal analysis.

Using the Subtotals Functionality

With your data sorted, you can now use the Subtotals functionality:

  • Select the entire dataset again.
  • Go to the “Data” menu and click on “Subtotals.”

Subtotals

In the “Subtotals” dialog box, you’ll see options for grouping and summarizing your data. By default, it may suggest using the first column for grouping, which is what you want in most cases.

Subtotals Dialog

  • In the “Function” dropdown, choose the type of summary you want, which is “Count” in this case.
  • Make sure that the “Replace current subtotals” option is selected.
  • Click “OK.”

LibreOffice Calc will now calculate the subtotal counts for each item in your dataset and insert them into your spreadsheet. It will also group items together and provide an outline to help you navigate the summary.

Subtotals Result

The Subtotals functionality creates a summary of your data by grouping items and counting them. You can expand and collapse these groups using the outlined symbols to the left of the spreadsheet. This allows you to view the summary data in a more organized manner.

The Subtotals functionality in LibreOffice Calc is a powerful tool for analyzing data and generating summary reports. Whether you’re working with product lists, customer data, or any other dataset, Subtotals can help you count how many times each item is repeated without the need for complex formulas or manual counting. By following the steps outlined in this blog post, you can harness the full potential of LibreOffice Calc and make your data analysis tasks more efficient and accurate. Give it a try, and you’ll be amazed at how Subtotals can streamline your data analysis workflow.