Using the i.MX27 video codec
From ArmadeusWiki
The i.MX27 (used on the APF27) has an internal DSP which can be used to encode/decode video stream, coming from various sources (CSI, buffer, etc...). To use it Freescale provides some useful tools.
Contents
Installation
$ make freescale-tools
- then reflash your rootfs and you will get some stuff in /usr/bin/vpu/
Usage
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Note: Currently, decoder/reader on the PC side has to be launched BEFORE the encoding tool on the APF27 (if using RTP stream) |
mxc_vpu_test.out (yeah Freescale has strange ways to name its executables ;-) ) allows you to decode/encode video streams. This tool needs a configuration file (some are given as examples).
- To encode video in H.264 and send it through Ethernet/RTP to a client with 192.168.0.17 IP:
# mxc_vpu_test.out -c codec.cfg.net.enc.vga.h264
with the following codec.cfg.net.enc.vga.h264 file:
1 ; Number of Codec 0 ; index 1 ; src, 0 file, 1 camera, 2 network /root/Kaleidoscope_h264_aac.m4v ;file name or IP, if src is camera, ignore this item. 2 ; dst, 0 file, 1 LCD, 2 network 192.168.0.17 ; act as server 1 ; 0=Dec, 1=Enc 25 ; fps in Hz, not used now 0 ; bitrate in Kbps (64, 128, 384), 0=auto 2 ; 0=Mpeg4, 1=H.263, 2=H.264 640 ; picWidth 480 ; picHeight 1 ; GopSize (0 only first frame is I, 1 all is I; 2: IPIP...), not used now 1200 ; frame_count, not used now 0 ; rot_angle; 1 ; out_ratio, to fit the screen 240*320 0 ; mirror, 0 none, 1 horizon, 2 vertical;
Decoding incoming streams on your PC
- Decoding an RTP H.264 stream coming in UDP on port 6666 and displaying it at original size:
$ gst-launch-0.10 udpsrc port=6666 caps="application/x-rtp, media=(string)video, clock-rate=(int)90000, encoding-name=(string)H264" \
! rtph264depay ! ffdec_h264 ! xvimagesink sync=false
- Decoding an RTP H.264 stream coming in UDP on port 6666 and displaying it in 320x240:
$ gst-launch-0.10 udpsrc port=6666 caps="application/x-rtp, media=(string)video, clock-rate=(int)90000, encoding-name=(string)H264" \
! rtph264depay ! ffdec_h264 ! videoscale ! video/x-raw-yuv, width=320, height=240 ! xvimagesink sync=false
Saving incoming streams on your PC
- Save an incoming H.264 RTP stream (port 6666) in a file:
$ gst-launch-0.10 udpsrc port=6666 caps="application/x-rtp, media=(string)video, clock-rate=(int)90000, encoding-name=(string)H264" \
! rtph264depay ! filesink location=./gst-test.264
Debugging incoming streams
- Activate debug (level 5) in rtph264depay module:
$ gst-launch-0.10 --gst-debug=rtph264depay:5 ...
- Activate debug (all modules):
$ gst-launch-0.10 --gst-debug-level=5 ...
