what are the disadvantages of H264?

Question

There are lot of articles available on net for understanding h264 and the advantages it provide.

From a practical implementation point of view, as visual communication is not only about video codec and much more things like resiliency, bandwidth etc etc, can you guys let me know what are the disadvantages of h264 / things that are not addressed in it?

Can you guys also throw some light on any other issues you have specifically faced with h264? (Interoperability between packet and circuit switched networks, interworking between vendors etc etc)

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Thanks for your insight guys..

As you have mentioned that H264 licensing involves a huge cost, do you people see VP8 (made royalty free) to capture the eyes of the media server vendors.?

Answer 1

Encoding and decoding complexity: H.264 encoding and decoding is more computationally complex than some other codecs such as MPEG-4 Part 2 (DivX, XviD). However, the compression performance of H.264 is significantly better than these so it depends on what is more important to you.

This is becoming less of a problem as more devices are including hardware support for H.264.

Error Resiliency: There are some things in H.264 to deal with bit errors, but often they are not used and a single bit error can still have a catastrophic effect. From what I have seen in my study of video codecs, error resiliency seems to being pushed to another layer in most systems. That is, the video codec is designed for maximum compression, and another layer is added on top of the video data to take care of bit errors. That way those who don't need the error resiliency don't pay for it with lower compression rates.

A common example of this is the DVB standard which uses MPEG-2 or H.264 coded video inside an MPEG-2 Transport Stream that contains a forward error correction scheme.

Licensing and Royalties: I am no expert (or even reasonably knowledgeable) in this area, but depending on your use case, you may have to pay some kind of royalty to encode to H.264 legally. See this.

Other than these, I really don't see any other disadvantages of H.264. It seems to be the state of the art for anything from internet quality streamed video to Blue-Ray HD video.

I can't really comment with regards to the last question (packet/circuit switched networks, interworking between vendors, etc.) since I have never actually built a hardware system to work with H.264. I will say that as long as the encoder creates a valid H.264 stream and you have a decoder that fully implements the standard, you should have no problem getting things to work together. This is the whole point of having a standard.