Bug 235030 – There is a big delay of video media stream if we share screen by getDisplayMedia in Safari from different MacOS desktops

• Status: NEW
• Component: WebRTC

[walter]

If we share screen by API "getDisplayMedia" in Safari on different MacOS desktops, there will be a big delay in the shared video media streaming.
In other words, If we share screen in Safari in same desktop, that’s ok.   

The problem is found on Safari15, MacOS 11.x/12.x with Intel CPU. 


# Steps:

1. Alice join an online meeting by Safari
2. Bob also join the online meeting by other browsers, such as Chrome, Firefox or Safari.
3. Alice start to share her screen, auto play a PPT or video clip, such as https://www.youtube.com/watch?v=b96TnabpVyo in full screen or in another desktop



# Expect Result:

Bob should see shared screen video normally.

# Actual Result:

After a while, Bob see shared screen video freeze frequently, sometimes, freeze time exceeds 60 seconds.

I wrote an example to duplicate the issue: https://github.com/walterfan/webrtc_remote_sharing

[Radar WebKit Bug Importer]

<rdar://problem/87339054>

[youenn fablet]

I tried the repro case, but I did not reproduce the freeze.
I am unclear whether freeze is happening on generation side (getDisplayMedia) or in the transmission chain.
Can you send me privately a sysdiagnose ([e-mail]) if you can reproduce on most recent MacOS version, with the timing of the freezes?

[walter]

Sorry for the confusion.  My local video file is large, so I give a youtube url. 
You need to download the video file and playback it in local in full screen or different desktop.

I can reproduce the issue 100%

Please let me know if you need any recording or sysdiagnose

[PhungDuong]

We also had the same problem with iPhone 7 iOS 14, and 15.

When joining a WebRTC video call and sharing screen, after about 30 minutes, the iPhone 7 gets hotter than usual, then the video on the share screen is delayed from 2 to 4 seconds. The audio also sounds laggy and unstable.

But with other devices like iPhone 6, iPhone 8, X, etc., it does not have the above problem.

[youenn fablet]

getDisplayMedia has changed a lot behind the scenes.
Is it still reproducing on recent macOS?
If not, we should probably close the bug.

[youenn fablet]

Closing as Configuration Change given the getDisplayMedia backend changed a lot. Please reopen if needed with repro steps (and or send a sysdiagnose privately to me).

[Martin Bartlett]

Your detailed steps and results indicate that the issue likely lies in the handling of screen sharing via the getDisplayMedia API in Safari on MacOS, particularly with Intel CPUs. It appears that the problem manifests when screen sharing involves media playback (like a YouTube video) in full screen or on another desktop, resulting in significant delays or freezing.
Update Software:

Ensure that both MacOS and Safari are updated to their latest versions. Safari 15 has known issues that might be resolved in subsequent updates.
Screen Resolution and Performance:

Lower the resolution of the shared screen or the quality of the video being played. High resolution and full-screen videos consume more resources, potentially leading to delays.
Browser Compatibility:

Test the screen sharing with different browsers on the MacOS devices involved. Sometimes, using Chrome or Firefox can yield better performance due to different implementations of WebRTC.
Optimize System Resources:

Close unnecessary applications and processes on Alice's machine to free up CPU and memory resources.
Network Conditions:

Ensure that both Alice and Bob have a stable and high-speed internet connection. Network instability can exacerbate the delay and freezing issues.
Technical Adjustments:
Throttling and Encoding Settings:

Adjust the encoding settings in your WebRTC implementation. Experiment with different bitrates and resolutions to find an optimal balance between quality and performance. https://snow-rider.io/
CPU Utilization: 

Monitor CPU utilization during the screen sharing session. High CPU usage on Alice’s machine might indicate that the system is struggling to handle the screen capture and encoding.
Safari Specific Workarounds:

Consider implementing Safari-specific workarounds or optimizations in your WebRTC code. Safari has some unique behaviors that might need tailored handling.
const constraints = {
  video: {
    frameRate: { ideal: 10, max: 15 },
    width: { ideal: 1280 },
    height: { ideal: 720 },
  },
  audio: false
};

navigator.mediaDevices.getDisplayMedia(constraints)
  .then(stream => {
    // Handle the shared stream
  })
  .catch(error => {
    console.error("Error accessing display media: ", error);
  });

Wow, that's a bummer about the Safari screen sharing delay! Hope they figure out a fix soon, 'cause screen sharing is super important these days. Sounds like a pain for anyone trying to collaborate.  https://crazy-cattle-3d.com/

Ah, the joys of tech! It’s like Safari decided to play hide and seek with our video streams. If you’re looking for some tools to aid your screen sharing woes, check out <a href="https://dirs.cc/" target="_blank">Dirs.cc</a>.

[FloCarson]

Created attachment 475448 [details]
From Bricks to Business: Mastering the Quirky Charm of Store Management Games Like Block Breaker


Store management games offer a unique blend of strategic thinking, resource management, and a satisfying sense of building something from the ground up. They can be surprisingly addictive, often wrapping mundane tasks like stocking shelves and setting prices in a compelling gameplay loop. And while the core mechanics might seem similar across different titles, the thematic twist and unique quirks are what make each game truly special. In this article, we'll explore the ins and outs of playing and enjoying store management games, using the delightful and decidedly unusual Block Breaker  as our primary example. Visit website https://blockbreaker.lol
Introduction: Beyond the Supermarket Sweep
Forget battling hordes of zombies or exploring fantastical realms. Store management games place you in the role of an entrepreneur, tasked with building a successful business, one product, employee, and customer at a time. These games appeal to our inner strategist, our organizational instincts, and our desire to see tangible results from our efforts. They offer a satisfying sense of progression, as your humble shop transforms into a bustling commercial hub.
What distinguishes Block Breaker from the crowd is its bizarre premise: you manage a store selling… well, blocks. Not just any blocks, but blocks that seem ripped straight out of a retro arcade game. This unusual theme adds a layer of whimsical charm to the classic store management formula, making it instantly appealing to those seeking something a little different.
Gameplay: Building Your Blocky Empire
The basic gameplay loop of most store management games, including Block Breaker, revolves around a few core elements:
Inventory Management: This is the bread and butter of any store management game. You need to purchase products (in Block Breaker's case, various types and colours of blocks), manage your stock levels, and ensure you have enough inventory to meet customer demand. Smart purchasing is crucial. Buying in bulk can often save you money, but too much stock can tie up capital and leave you vulnerable to changing customer preferences.
Pricing: Finding the sweet spot between attracting customers and maximizing profit is a constant balancing act. Lower prices can boost sales volume, but higher prices can lead to greater profit margins. Block Breaker likely offers tools to track customer demand and help you fine-tune your pricing strategy. Experimentation is key!
Store Layout and Design: A well-organized store is a happy store. How you arrange your shelves, displays, and aisles can significantly impact customer flow and purchasing behaviour. In Block Breaker, this might mean strategically placing particularly appealing or rare blocks to entice customers and encourage them to explore your inventory. Think about how you want to guide shoppers through your store and make it as convenient as possible for them to find what they're looking for.
Employee Management: As your store grows, you'll need to hire employees to help with tasks like stocking shelves, managing the cash register, and providing customer service. Each employee may have different skills and levels of expertise, and you'll need to allocate them effectively to maximize their contribution. Block Breaker might introduce unique employee types with special abilities that complement the block-selling theme.
Upgrades and Expansion: Reinvesting your profits into store upgrades is essential for long-term growth. This might involve purchasing new shelves, expanding your store space, or acquiring new technologies that improve efficiency or attract more customers. In Block Breaker, upgrades might unlock new types of blocks to sell or special displays that boost their appeal.
Meeting Customer Demands: Paying attention to what customers are buying (and not buying!) is crucial. Trends change, and you need to adapt your inventory and pricing to stay ahead of the curve. Block Breaker may present you with specific customer requests or market events that require you to be nimble and responsive.
Tips for Block-Breaking Success (and General Store Management Wisdom)
Here are some tips to help you master store management games like Block Breaker:
Start Small, Think Big: Don't try to do everything at once. Focus on mastering the basics of inventory management and pricing before expanding your operations.
Track Your Data: Pay close attention to your sales figures, inventory levels, and customer feedback. This data will provide valuable insights into what's working and what's not.
Experiment and Adapt: Don't be afraid to try different strategies and see what works best for you. The market is constantly changing, so you need to be flexible and adapt to new trends and customer demands.
Invest Wisely: Don't waste your money on unnecessary upgrades or expansions. Focus on investing in areas that will have the biggest impact on your bottom line.
Keep Your Customers Happy: Customer satisfaction is key to long-term success. Provide excellent service, offer competitive prices, and create a pleasant shopping experience.
Automate where possible: As your store grows, look for ways to automate tasks to free up your time and resources. This might involve hiring employees or investing in new technologies.
Pay attention to the unique mechanics: Each store management game has its own unique twists and features. In Block Breaker, understand how the different types of blocks affect customer demand and optimize your store layout accordingly. Read any tutorials or in-game tips carefully.
Conclusion: Build Your Own Empire (One Block at a Time)
Store management games like Block Breaker offer a surprisingly engaging and rewarding experience. They challenge you to think strategically, manage resources effectively, and build something from nothing. While the core mechanics might seem simple at first, the depth and complexity of these games can be surprisingly addictive. By following the tips outlined above and embracing the unique quirks of your chosen game, you can build your own thriving business and achieve store management mastery. So, dive in, stock those shelves, set those prices, and get ready to turn bricks (or blocks!) into business. And if you are ready for a quirky experience check out Block Breaker