Recording CBR vs CQP: Is CQP better than CBR? Is It Worth It? (See Description)

Introduction

In this tutorial, we will explore the differences between Constant Bit Rate (CBR) and Constant Quality Parameter (CQP) video encoding methods. We'll analyze a series of tests conducted using Tom Clancy's The Division to determine whether CQP provides better quality compared to CBR. This guide will help you understand the implications of each method on video recording and streaming.

Step 1: Understand Encoding Methods

• Constant Bit Rate (CBR): This method maintains a fixed bit rate throughout the video, which can lead to larger file sizes for high-motion scenes but ensures consistent quality.
• Constant Quality Parameter (CQP): CQP adjusts the bit rate dynamically based on the complexity of the scene, aiming for a consistent quality level, which can reduce file sizes during less complex scenes.

Practical Tip

• For live streaming or scenarios where bandwidth is limited, CBR may be preferable for its predictability. For recorded content where quality is paramount, consider CQP.

Step 2: Set Up Your Testing Environment

• Recording Setup:

  • Use a reliable encoder (e.g., NVENC on a GTX 1060 GPU).
  • Ensure your recording software is configured correctly to handle both CBR and CQP settings.

• Test Conditions:

  • Test One: Record a 2-minute video in low-light conditions with movement.
  • Test Two: Record a 1-minute video in the same environment but with minimal movement.

Practical Advice

• Keep lighting and scene complexity consistent between tests to isolate the effects of the encoding method on quality.

Step 3: Conduct the Tests

• Test One:

  • Video 1: 1440p60, NVENC, High Quality Preset at CBR 34000 kbps.
  • Video 2: 1440p60, NVENC, High Quality Preset at CQP 10.

• Test Two:

  • Video 1: 1440p60, NVENC, High Quality Preset at CBR 34000 kbps.
  • Video 2: 1440p60, NVENC, High Quality Preset at CQP 10.

Video Links for Reference

• CBR3400 Motion: Watch Here
• CQP10 Motion: Watch Here
• CBR3400 Still: Watch Here
• CQP10 Still: Watch Here

Step 4: Analyze Rendering Times

• Compare rendering times for each encoding method:
  • CBR34000 Motion: 8:43 minutes
  • CQP10 Motion: 10:49 minutes
  • CBR34000 Still: 2:02 minutes
  • CQP10 Still: 2:15 minutes

Key Insights

• CBR generally renders faster than CQP, but the quality may vary depending on the scene complexity.

Step 5: Review the Results

• Assess the visual quality of each video by watching the samples.
• Consider factors such as compression artifacts, clarity, and overall appearance in both high-motion and still scenarios.

Common Pitfalls to Avoid

• Do not overlook the importance of scene complexity when evaluating quality.
• Ensure your playback settings match the recorded resolution for accurate comparisons.

Conclusion

In summary, both CBR and CQP have their advantages depending on the context of use. CBR provides consistent quality suitable for streaming, while CQP allows for better quality management in varied scene complexities. Experiment with both methods to determine which suits your specific needs best.

Next Steps

• Consider testing different bit rates and quality settings in your recordings.
• Assess your hardware capabilities to choose the most suitable encoder for your projects.