Friday, June 24, 2011

Not all H.264 is Created Equal

Despite being the latest video compression technology standard, the actual performance of H.264 varies significantly. The amount of compression and the resulting image quality are dependent on how it is implemented.

That’s why Bosch employs a superior form of H.264, putting the best this technology has to offer into our H.264 products. This ensures maximum savings in storage and bandwidth, while maintaining the highest possible image quality. The H.264 standard includes several profiles, each one comprising a number of "blocks." Some blocks are optional but Bosch incorporates all blocks belonging to a profile to maximize coding benefits.

Two profiles – Baseline and Main – are relevant to video surveillance. In addition, we have our own implementation of Baseline, known as Baseline Plus.

Standard Baseline profile
The standard Baseline profile is the minimum recommendation for H.264 video implementation. It does not support interlaced video (field coding) therefore the maximum resolution is limited to 2CIF. Even so, it delivers powerful compression capability, reducing storage
requirements by up to 30% compared to MPEG-4. Baseline profile is only used on cameras and encoders without hardware accelleration for H.264.

Bosch Baseline Plus profile
By incorporating an extra element – a field coding block – that supports interlacing and improves frame rate, our H.264 Baseline Plus profile increases resolution to full 4CIF while maintaining the same level of video compression as the Baseline profile.

Bosch Main profile
Offering up to 50% greater compression efficiency compared to MPEG-4, without sacrificing image quality, the Main profile is the top-of-the-line H.264 implementation. However, as it utilizes all coding blocks, it does mean that devices supporting Main profile need to have powerful processing performance.

Learn more at http://ow.ly/5pC6d.

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