mpeg-4 | 易学教程

MPMoviePlayerController H.264 and Multiple Audio Streams

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问题 I am trying to find some information on how to support multiple audio streams from a single H.264/MPEG4 video file. So far I have found very little information when googling, I was wondering if anybody has any information that may shed some light. I would like to display the video then have a choice of which audio stream to play from the H.264 format. Anybody? 回答1: MPMoviePlayer cannot be used to play a movie with multiple audio streams. 来源： https://stackoverflow.com/questions/15138380

How is a h264 idea bitstream organized? / header start codes

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问题 I was trying to learn a bit about h264 by looking at the bitstream of a video file with a hex editor. I found here the start codes for a video object planes (0x000001b6) and for i-frames (0x000001b600). But I can't find many of those bytes in video files. Most of the time those start codes appear at the beginning of a file with only a few bites in between. I expected them to show up very regularly, in equal distance all over the file!? Is is even ok to look at a file with a hex editor this

MPEG-4 Part 2 had some awesome face- and body- motion concepts, but they disappeared in MPEG-4 Part 10 (H.264). Why?

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问题 During the last few weeks, I had the opportunity to read two documents: The MPEG-4 Part 2 specification (ISO/IEC 14496-2), which people just call "mpeg-4" The MPEG-4 Part 10 specification (ISO/IEC 14496-10), which is also called "h.264" or "AVC" After having read all the cool ideas in "mpeg-4" like identifying facial expression, motion of limbs of people, and sprites, I got really excited. The ideas sound very fun, maybe even fantastic, for an idea from 1999. But then I read the "h.264"

Get Stream and save as jpeg (image) file from IP Camera using ffmpeg

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问题 How i can get stream from Ip Camera, Its using RTP, stream is MPEG4, i have multicast address and port,and i have ip camera's IP address and Port Number. And I cant reach via http forexample (http://ip/jpeg) And I cant reach stream with VLC Player too. forexample (rtp://ipadressofcam:port) and ( rtp://multicastaddress:port ) So What is ffmpeg command of that? I have windows OS, I only write code with C# right now. But producer created their own ocx which used for viewing cam,that plugin can

stream live video from IP Cams in iPhone SDK?

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I have to develop plug-in module which will allow us to stream live video from IP Cams if the IP of the cameras are available. The format and encoding for the same is: MPEG4 RTSP/RTP but I dont know from where to start. I have search in many site, unable to find any thing related. while browsing the Apples doc's, I found AVFoundation is used to stream live video from IP Cam's. UPDATE I found this from GITHUB but dont know How to implement it in my App. Please help me by sample code or related app and suggest me to overcome this. thanks in Advance. Dipan Mehta I am adding some references for

MPEG4 extract from RTP payload

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I'm trying to extract mpeg4 from an rtp payload , format of the rtsp media (video) is MP4V-ES but I'm not able to extract the mp4 from the payload . when I dump the extract into a raw file and use ffmpeg to convert it into .avi or .mpg its not working. I don't know what I'm missing here. the code is written in java. I want to extract each video frame from the rtp and save that in a file or retransmit it. Thanks Question UPDATED..... Thanks for the inputs, actually I'm able to extract bytes from 000001b6 and sent it to ffmpeg , but it complains about not header information and then I

Android: mpeg4/H.264 packetization example

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I need to split mpeg4 video stream (actually from android video camera) to send it through RTP. The specification is little large for quick reference. I wonder if there any example/open source code for mpeg4 packetization? Thanks for any help ! Mpeg4 file format is also called ISO/IEC 14496-14. Google it any you will find specifications. However, what you are trying to do (RTP publisher) will be hard for the following reasons: Mpeg4 has header at the end of the file. Which means header will be written out only when video stream is finished. Since you want to do real time video streaming you

Creating MPEG4 video file with Python from raw frames

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问题 I have a raw video frame source which I can access in Python. I'd like to create a MPEG4 video out of this, with MP3 background music. What kind of tools and libraries are available in Python for such a task? Preferably I'd like to have an API for which I can feed output filename and then individual frames as 24 bit raw images. 回答1: With OpenCV and the corresponding Python binding, you could use something like the function cv.WriteFrame . You could also use pyffmpeg, but that is geared more

Can you find key frame (I-frame) in h264 video without decoding? i.e. is it in packet?

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I need to know if I can find a I-frame without having to decode it first. I would like there to be some flag in AVPacket, but I can't see that there is one. Thanks. You can certainly find location of I frame by looking up appropriate header code. If you parse the sequence you can find it from the start code. The H.264 bitstream is broken into sections called NAL units. These units have the 24 bit code 0x000001 preceding them for synchronization. After this there will be a unique start code that corresponds to start of a picture, and type of picture based on which you can decide which frame is

MPEG-4 Part 2 had some awesome face- and body- motion concepts, but they disappeared in MPEG-4 Part 10 (H.264). Why?

阅读更多关于 MPEG-4 Part 2 had some awesome face- and body- motion concepts, but they disappeared in MPEG-4 Part 10 (H.264). Why?

During the last few weeks, I had the opportunity to read two documents: The MPEG-4 Part 2 specification (ISO/IEC 14496-2), which people just call "mpeg-4" The MPEG-4 Part 10 specification (ISO/IEC 14496-10), which is also called "h.264" or "AVC" After having read all the cool ideas in "mpeg-4" like identifying facial expression, motion of limbs of people, and sprites, I got really excited. The ideas sound very fun, maybe even fantastic, for an idea from 1999. But then I read the "h.264" standard, and none of those ideas were there. There was a lot of discussion on how to encode pixels, but