1. H.264 / MPEG-4 Part 10
Nimrod Peleg
March 2003

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7. Previous Standards

8. H.264 Brief review Goal Start from zero. No backward compatibility.
Develop a high-performance video coding standard.
Start from zero.
No backward compatibility.
Assumptions
Block based.
Software implementation.
Network friendly.

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10. Transform DCT like. Integer arithmetic only.
without multiplications.
Optional use of a 4x4 transform block size.

11. Quantization Compounding quantization step.
Thirty-two different quantization step sizes.
The step sizes are increased at a compounding rate of approximately 12.5%.
Different quantizer for luminance, chrominance.
Two different coefficient-scanning patterns.
The simple zigzag scan.
The double scan.

12. Frames Store
The H.264 standard offers the option of having multiple reference frames in inter picture coding.
Up to five different reference frames could be selected.
Resulting in better subjective video quality and more efficient coding of the video frame under consideration.
Using multiple reference frames might help making the H.264 bit-stream error resilient.

13. Motion Estimation & Compensation
Motion Estimation is where H.264 makes most of its gains in coding efficiency.
Quarter pixel accurate motion compensation.
Translation only.
The standard does not determine which algorithm should be used.

14. Motion Estimation & Compensation
Seven optional modes.
Different modes of dividing a macroblock for motion estimation in H.264

15. Entropy Coding H.264 has adopted two approaches for entropy coding :
Universal Variable Length Codes (UVLCs)
One table.
Context-Based Adaptive Binary Arithmetic Coding (CABAC)

16. Intra prediction 9 optional prediction modes for each 4x4 luma block.
4 optional modes for a 16x16 luma block.
4 optional prediction modes for a 8x8 chroma component.
One mode for 4x4 chroma block.

17. Summery Transform Quantizer Motion estimation and compensation IDCT
Optional use of a 4x4 transform block size.
Quantizer
step sizes are increased at a compounding rate of approximately 12.5%.
Two coefficient-scanning patterns.
Motion estimation and compensation
Translation only.
A number of different block sizes are used for motion prediction.
Quarter pixel positions are used for motion prediction.

18. Summery Frames store Entropy coding
Multiple reference frames may be used for prediction.
Entropy coding
Only one regular VLC is used for symbol coding.