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FFMPEG [SHELL CMD] cutting last x frames [SHELL CMD] combining videos
25 avril 2014, par user1708604.mp4 videos in 1920 x 1080, 25 frames / second different length
Two commands needed:
0) One command should delete x frames from the end of the video and create a new video without the last x frames as .mp4, save it in folder y 1) One command should combine x amount of videos to one new video
Just for info: I am using Python to call ffmpeg. Platform: Windows or CentOS.
Many thanks in advance. :)
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openRTSP TCP 100% Cpu
25 avril 2014, par user1199722First thanks for the great work for live media group. I am currently facing a problem with OpenRTSP utilizing cpu 100%. I am using the following commands to stream from remote ipcamera through internet. It works fine with local cameras. But when I try to stream from Internet IP camera (720p), At random times openRTSP start uses 100% cpu and stops output of streaming. The process is not exiting it stay with 100% cpu.
I have observed that stream stops with a series of "c9c99c999......." I am using TCP streaming of rtsp. Please find the command that i am using.
openRTSP -d 60 -v -t -c -b 800000 | ~/bin/ffmpeg -r 15 -i - -codec copy -hls_list_size 65535 -hls_time 5
Please provide your suggestions regarding the problem Waiting for your valuable pointers.
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Encode video for ipod classic
25 avril 2014, par mulllhausenI just finished installing
ffmpegon debian wheezy using these instructions - http://trac.ffmpeg.org/wiki/UbuntuCompilationGuide. Now I want to encode a video to play on my iPod classic. The video has the following info:$ mediainfo in.mp4 General Complete name : in.mp4 Format : MPEG-4 Format profile : Base Media / Version 2 Codec ID : mp42 File size : 1.21 GiB Duration : 55mn 10s Overall bit rate mode : Variable Overall bit rate : 3 130 Kbps Encoded date : UTC 2010-08-25 23:38:59 Tagged date : UTC 2010-08-25 23:38:59 Video ID : 1 Format : AVC Format/Info : Advanced Video Codec Format profile : High@L3.2 Format settings, CABAC : Yes Format settings, ReFrames : 2 frames Codec ID : avc1 Codec ID/Info : Advanced Video Coding Duration : 55mn 10s Bit rate mode : Variable Bit rate : 3 000 Kbps Maximum bit rate : 5 000 Kbps Width : 1 280 pixels Height : 720 pixels Display aspect ratio : 16:9 Frame rate mode : Constant Frame rate : 29.970 fps Standard : NTSC Color space : YUV Chroma subsampling : 4:2:0 Bit depth : 8 bits Scan type : Progressive Bits/(Pixel*Frame) : 0.109 Stream size : 1.16 GiB (96%) Language : English Encoded date : UTC 2010-07-21 13:28:49 Tagged date : UTC 2010-07-21 13:28:49 Color primaries : BT.709-5, BT.1361, IEC 61966-2-4, SMPTE RP177 Transfer characteristics : BT.709-5, BT.1361 Matrix coefficients : BT.709-5, BT.1361, IEC 61966-2-4 709, SMPTE RP177 Audio ID : 2 Format : AAC Format/Info : Advanced Audio Codec Format profile : LC Codec ID : 40 Duration : 55mn 10s Bit rate mode : Variable Bit rate : 125 Kbps Maximum bit rate : 270 Kbps Channel(s) : 2 channels Channel positions : Front: L R Sampling rate : 44.1 KHz Compression mode : Lossy Stream size : 49.4 MiB (4%) Language : English Encoded date : UTC 2010-07-21 13:28:49 Tagged date : UTC 2010-07-21 13:28:49 mdhd_Duration : 3310353I have already tried just copying the video to the IPod with
bansheebut the video just shows a black screen. Which is the best format to play the video on the Ipod? What ffmpeg parameters should I use? I would like to maximize resolution while minimizing file size. -
rtp decoding issue on p frames
24 avril 2014, par user3569521I am streaming an rtsp stream from an IP camera. I have a parser which packages the data into frames based on the rtp payload type. The parser is able to process I frames since these contain the start of frame and end of frame packets, as well as packets in between (this is FU-A payload type).
These are combined to create a complete frame. The problem comes in when I try to construct P frames, from the wireshark dump some of these appear to be fragmented (FU-A payload type) these contain the start of frame and end of frame packets, however these do not contain packets in between. Also in some instances the camera sends strange marked packets with a payload type 1, this according to my understanding should be a complete frame.
Upon processing these two versions of P frames I then use ffmpeg to attempt to decode the frames, I receive errors messages like top block unavailable for intra mode 4x4.
At first I thought this could be due to an old ffmpeg version but I searched the web and recompiled ffmpeg with the same problem.
The I frames appear fragmented and contain lots of packets, some P frame have a start of frame (0x81) and EOF (0x41) but no packets in between and some just looked corrupt starting with 0x41 (seems like this should be the second byte) which gives payload type of 1. I am a novice when it comes to these issues but I looked at rtp documentation and I cannot find an issue with how I handle the data.
Also I stream from VLC and this seems fine but appears to halve the frame rate, I am not sure how they are able to reconstruct frames.
Please could someone help.
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FFMPEG : Smooth streaming on IOS and Android
24 avril 2014, par VprnlI am transcoding a file to the ISMV "smooth streaming" format to create fragmented MP4 files.
The Ffmpeg parameters I use are the following:
ffmpeg -i "'+inputUrl+'" -g 52 -threads 0 \ -vcodec libx264 -coder 0 -flags -loop -pix_fmt yuv420p \ -crf 22 -subq 0 -sc_threshold 0 -s 1280x720 -profile:v baseline \ -keyint_min 150 -deinterlace -maxrate 10000000 -bufsize 10000000 \ -b 1200k -acodec aac -ar 48000 -ab 192k -strict experimental \ -movflags +frag_keyframe+empty_moov '+outputUrlThe main purpose is to play the file while transcoding. This works great on my desktop. Sadly though, this can not be said for Android and IOS devices. It simply does not play anything.
Is it possible to play a fragmented mp4 on these devices?
