how to insert an i-frame in AVIDEMUX2

[shparekh]

I am editing clips so that they could be indexed and played in IOS devices. Apple's IOS's media player can jump to key frames and also create thumbnails from those frames. The source clips that I work with do not always have key frames at the positions that I would like to index into in IOS. Therefore, I want to insert key frames first into the video, encode it and then load into the IOS device.

I am new to AVIDEMUX2 and novice when it comes to video editing. So I would appreciate any guidance.

Thank you.
best regards.

[filmboss80]

I have to ask: do you understand what an I-frame is? Are you familiar with GOPs? This might help:

http://en.wikipedia.org/wiki/Group_of_pictures

I-frames are created at the encoding level. They are not something that can simply be inserted into an existing video stream through editing.

[shparekh]

Thx. I understand that much. I am prepared to encode the clip. In most cases I have to resize the video anyway to fit smaller screens of iPods and iPhones.

[pandy]

i dont remeber which tool is able to recode only required GOP thus You can add keyframe anywhere and only required frames are recoded.

[shparekh]

Did I understand you correctly that even during the encode process the GOPs are maintained? Is there fundamentally a problem with what I am trying to do?

[pandy]

nope - most of codecs allow to cut stream with key frame accuracy ie with respect to GOP - this kind of operation is very fast because there is no need to re compress video - in case when cutting point is arbitrary to GOP structure You need to decode/cut/encode - some smart tools offer kind of hybrid mode - they cut with respect to GOP very fast and only necessary part of arbitrary selected cut point is re encoded thus only modified GOP not the whole stream need to be re encoded.

If you fully re encode stream then GOP structure is not a limitation.