Published Book on Amazon
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All of IOT Starting with the Latest Raspberry Pi from Beginner to Advanced – Volume 1 |
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All of IOT Starting with the Latest Raspberry Pi from Beginner to Advanced – Volume 2 |
출판된 한글판 도서
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최신 라즈베리파이(Raspberry Pi)로 시작하는 사물인터넷(IOT)의 모든 것 – 초보에서 고급까지 (상) |
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최신 라즈베리파이(Raspberry Pi)로 시작하는 사물인터넷(IOT)의 모든 것 – 초보에서 고급까지 (하) |
Original Book Contents
22.1.5 Converting Video Format Using <FFMPEG> Program
Video taken by Raspberry Pi camera use "H.264" format, which is a format that is not widely used by ordinary users. You can use <FFMPEG> program to convert it to a popular video format.
● Installing <FFMPEG> program
To use <FFMPEG> program, you need to install it as follows:
[Command Format]
| sudo apt-get install ffmpeg |
If you execute the command, it checks installation of the program and confirms whether or not to install the program. If you choose "Continue", the installation process begins as shown below.
| pi@raspberrypi ~ $ sudo apt-get install ffmpeg |
| Reading package lists... Done Building dependency tree Reading state information... Done ~ ~ Skip ~ 0 upgraded, 8 newly installed, 0 to remove and 39 not upgraded. Need to get 5,174 kB of archives. After this operation, 13.4 MB of additional disk space will be used. Do you want to continue [Y/n]? y ~ ~ Skip ~ Setting up libavfilter2:armhf (6:0.8.17-1+rpi1) ... Setting up ffmpeg (6:0.8.17-1+rpi1) ... W: Operation was interrupted before it could finish |
● Converting video format
To convert a video using <FFMPEG> program, use the command in the format as follows.
[Command Format]
| ffmpeg [[in-file option] [-I in-file] [out-file options] out-file |
[Command Overview]
■ This converts the specified video to a file of a different format.
■ User privilege -- Normal user.
[Detail Description]
■ None
[Main option]
| -h, -?, -help, --help | Show help. |
| -formats | Show available formats. The fields preceding the format names have the following meanings: D Decoding available E Encoding available |
| -codecs | Show available codecs. The fields preceding the codec names have the following meanings: D Decoding available E Encoding available V/A/S Video/audio/subtitle codec |
| -i filename | input file name |
| -vframes number | Set the number of video frames to record. |
| -r fps | Set frame rate (Hz value, fraction or abbreviation), (default = 25). |
| -s size | Set frame size. The format is wxh (avserver default = 160x128, ffmpeg default = same as source). The following abbreviations are recognized: |
| -vcodec codec | Force video codec to codec. Use the "copy" special value to tell that the raw codec data must be copied as is. |
[Used Example]
In this example, we will convert video of "H.264" format taken previously in Raspberry Pi to MKV format.
| pi@raspberrypi ~/Image_Camera $ ffmpeg -r 30 -i test_motion1.h264 -vcodec copy test_motion1.mkv |
| ffmpeg version 0.8.17-6:0.8.17-1+rpi1, Copyright (c) 2000-2014 the Libav developers built on Mar 25 2015 00:39:58 with gcc 4.6.3 The ffmpeg program is only provided for script compatibility and will be removed in a future release. It has been deprecated in the Libav project to allow for incompatible Shell syntax improvements in its replacement called avconv (see Changelog for details). Please use avconv instead. [h264 @ 0x480660] Estimating duration from bitrate, this may be inaccurate
Seems stream 0 codec frame rate differs from container frame rate: 2400000.00 (2400000/1) -> 30.00 (30/1) Input #0, h264, from 'test_motion.h264': Duration: N/A, bitrate: N/A Stream #0.0: Video: h264 (High), yuv420p, 1920x1080, 30 fps, 30 tbr, 1200k tbn, 2400k tbc Output #0, matroska, to 'test_modion.mkv': Metadata: encoder : Lavf53.21.1 Stream #0.0: Video: libx264, yuv420p, 1920x1080, q=2-31, 1k tbn, 1200k tbc Stream mapping: Stream #0.0 -> #0.0 Press ctrl-c to stop encoding frame= 142 fps= 0 q=-1.0 Lsize= 9844kB time=10000000000.00 bitrate= 0.0kbits/s video:9842kB audio:0kB global headers:0kB muxing overhead 0.017483% |
If you check after completing the operation, you can see that MKV file is newly created as below.
| pi@raspberrypi ~/Image_Camera $ ls -l |
| -rw-r--r-- 1 pi pi 10080058 May 13 16:11 test_motion1.mkv -rw-r--r-- 1 pi pi 10078296 May 13 14:51 test_motion1.h264 |
Now, if you play the vedo file of MKV format, you can view the contents as follows.
Figure 22‑5 Playing video using MKV file