Video/Image processing on Apple iPhone4

Question

I know iPhone 4 supports H.264 and MPEG-4 as video codecs, and JPEG and M-JPEG as image codecs.

I'm looking to get some information on the iPhone 4's video and image codecs and processing chips/SoC parts.

1. Does anyone know which vendor provides the SoC's to enable image/video compression and processing on the iPhone 4?

2. Are the video/image codec solutions - 'Software codecs' on a specialized dsp-core/processor or hard-wired as in a FPGA/ASIC solution?

Any pointers would be useful.

Answer 1

I think you'll get the answer in the iPhone 4 teardown that the guys at iFixit did sometime ago:

http://www.ifixit.com/Teardown/iPhone-4-Teardown/3130/1

You will be able to see there what components are inside the iPhone 4, but I'd guess all the video compression/decompression is processed by the A4 processor (an ARM Cortex A8 core variant).

http://www.ifixit.com/Teardown/Apple-A4-Teardown/2204/1

Answer 2

Goldenmean-

It's hard to determine, isn't it? No credible online documentation for A4 cores other than ARM + Imagine Tech.

As far as I can tell, Apple currently provides frame (stream) based H.264 decode API, but not encode. That could be because there's not enough horsepower for multiparty video conf (encode + multiple decode)... or it could just be there is a hardware-assist encode but Apple doesn't want to make it visible through APIs (royalty/licensing issues come to mind).

Our calculations show NEON is not enough for multiparty video conf -- or at best it may work but shut down everything else.

-Jeff