3gp and MP4

[Lele-brz]

Hi all,
Having to choose for a container to use for streaming video (using HTTP) to a mobile (Iphone), what do you think are the reasons to use 3gp instead o MP4?
I'm not sure how the two differs (couldn't find in the Sticky: MP4 FAQ)

Thanks in advance

[Drachir]

The main difference between 3GP and MP4, is the Object Descriptor Framework used by MP4. Cell Phones don't support the Object Descriptor Framework, so it make no sense to use the MP4 file format - use 3GP.

Some mobile phones have less cache space and don't support progressive download via http. For live streams and bigger files I would use rtsp(rtp).

Didn't saw the iPhone, the iPhone is doesn't support rtsp. But the iPhone is an exception most other mobile phones like the HTC Touch Diamond or cell phones from Nokia, Sonny Ericsson ... support rtsp.

[Lele-brz]

Thanks for answering,
In my case mp4 is ok for the Iphone, the only thing that I would like to reduce is the MP4 header overhead.
On large videos to start playing takes long because of the big header to download.
With same video and audio track Matroska has a much smaller header.
Bye

[bond]

On large videos to start playing takes long because of the big header to download.
With same video and audio track Matroska has a much smaller header.
With same video and audio track Matroska has a much smaller header.you are always making these claims. Still i neither get the "big overhead", nor a bigger overhead with mp4 compared to mkv here:
http://forum.doom9.org/showthread.php?t=101451

[Lele-brz]

Hi,
I'll be more precise, what I'm measuring is the size of the file to load before start decoding audio/video packets.
Checking with libav I could trace the bytes accessed during the open of the file (before start decoding packets).
What I noticed is that MKV has a much smaller header (not overhead):

Both files have the same h264 track and aac track.
mp4 was multiplexed with MP4Box,
mkv was multiplexed with AVI-MUX GUI (the only one that let me put the CuePoints at the beginning of the file)

Sheryl.mp4 filesize: 310,960,128 bytes - header size : 1572864 bytes
Sheryl.mkv filesize: 311,635,968 bytes - header size : 131695 bytes

Considering to stream HTTP the files I would prefer the mkv.