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Introduction

On this page you are going to find a set of pipelines used on the DM8168 (EVM and Z3 boards) and DM8148 (EVM). You could find pipelines regarding to H264 encoding and decoding, up and down scaling, video capture through v4l2 and OMX, and video streaming. All of these pipeline were tested in the DM8168 and DM8148 platforms with several resolutions and framerates.

DM81xx

Omx H264 encoding

With the omxh264 encoder we are able to encode raw video into H264 frames using different parameters to obtain the desired configuration.

Encode videotest pattern in H.264 (without container)

 
gst-launch-1.0 videotestsrc num-buffers=1000 ! omxbufferalloc num-buffers=8 ! omxh264enc ! perf print-arm-load=true ! filesink location=sample.h264

Encode videotest pattern in H.264 (with container)

 
gst-launch-1.0 videotestsrc num-buffers=1000 ! omxbufferalloc num-buffers=8 ! omxh264enc ! perf print-arm-load=true ! queue ! rrh264parser single-nalu=true \
! mp4mux dts-method=0 ! filesink location=test.mp4 -v

Single Video test source RTP/H264 streaming

These instructions show how to do video streaming over the network, a video will be played on the board and viewed on the host. These pipelines use a configured port to send the packets.

Stream H.264 video test pattern over RTP

Server: DM81xx

HOST=<Your IP address>

PORT=<The port to use>

gst-launch-1.0 videotestsrc ! 'video/x-raw,format =(string)NV12,width=1280,height=720,framerate=(fraction)60/1' ! perf print-arm-load=true ! omxbufferalloc num-buffers=12 ! omxh264enc \
i-period=30 idr-period=30 ! rtph264pay ! udpsink host=$HOST port=$PORT sync=false async=false -v

This pipeline is going to print the capabilities of each element's pad thanks to the -v option. The pipeline should print something similar to this output:

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/GstPipeline:pipeline0/GstOMXH264Enc-omxh264enc:omxh264enc-omxh264enc0.GstPad:src: caps = "video/x-h264\,\ stream-format\=\(string\)byte-stream\,\ alignment\=\(string\)au\,\ profile\=\(string\)baseline\,\ level\=\(string\)4.2\,\ width\=\(int\)1280\,\ height\=\(int\)720\,\ pixel-aspect-ratio\=\(fraction\)1/1\,\ framerate\=\(fraction\)60/1"
/GstPipeline:pipeline0/GstRtpH264Pay:rtph264pay0.GstPad:sink: caps = "video/x-h264\,\ stream-format\=\(string\)byte-stream\,\ alignment\=\(string\)au\,\ profile\=\(string\)baseline\,\ level\=\(string\)4.2\,\ width\=\(int\)1280\,\ height\=\(int\)720\,\ pixel-aspect-ratio\=\(fraction\)1/1\,\ framerate\=\(fraction\)60/1"
/GstPipeline:pipeline0/GstRtpH264Pay:rtph264pay0.GstPad:src: caps = "application/x-rtp\,\ media\=\(string\)video\,\ payload\=\(int\)96\,\ clock-rate\=\(int\)90000\,\ encoding-name\=\(string\)H264\,\ ssrc\=\(uint\)2286224513\,\ timestamp-offset\=\(uint\)3885907970\,\ seqnum-offset\=\(uint\)24314"
/GstPipeline:pipeline0/GstUDPSink:udpsink0.GstPad:sink: caps = "application/x-rtp\,\ media\=\(string\)video\,\ payload\=\(int\)96\,\ clock-rate\=\(int\)90000\,\ encoding-name\=\(string\)H264\,\ ssrc\=\(uint\)2286224513\,\ timestamp-offset\=\(uint\)3885907970\,\ seqnum-offset\=\(uint\)24314"
/GstPipeline:pipeline0/GstRtpH264Pay:rtph264pay0.GstPad:src: caps = "application/x-rtp\,\ media\=\(string\)video\,\ clock-rate\=\(int\)90000\,\ encoding-name\=\(string\)H264\,\ packetization-mode\=\(string\)1\,\ sprop-parameter-sets\=\(string\)\"J0KAKouVAKALcgA\\\=\\\,KN4BriAA\"\,\ payload\=\(int\)96\,\ seqnum-offset\=\(uint\)24314\,\ timestamp-offset\=\(uint\)3885907970\,\ ssrc\=\(uint\)2286224513"
/GstPipeline:pipeline0/GstUDPSink:udpsink0.GstPad:sink: caps = "application/x-rtp\,\ media\=\(string\)video\,\ clock-rate\=\(int\)90000\,\ encoding-name\=\(string\)H264\,\ packetization-mode\=\(string\)1\,\ sprop-parameter-sets\=\(string\)\"J0KAKouVAKALcgA\\\=\\\,KN4BriAA\"\,\ payload\=\(int\)96\,\ seqnum-offset\=\(uint\)24314\,\ timestamp-offset\=\(uint\)3885907970\,\ ssrc\=\(uint\)2286224513"
/GstPipeline:pipeline0/GstRtpH264Pay:rtph264pay0: timestamp = 3885907970
/GstPipeline:pipeline0/GstRtpH264Pay:rtph264pay0: seqnum = 24314
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.

You need the udpsink:sink capabilities for the client pipeline.

Client: Ubuntu PC

Copy the udpsink caps given by the server pipeline, erase the spaces and the (uint) cast.

CAPS="application/x-rtp,media=(string)video,payload=(int)96,clock-rate=(int)90000,encoding-name=(string)H264, \
ssrc=(int)2286224513,timestamp-offset=(int)3885907970,seqnum-offset=(int)24314"

PORT=<Port configured in the server>

gst-launch-1.0 udpsrc port=$PORT ! $CAPS  ! rtph264depay ! queue ! avdec_h264 ! xvimagesink sync=true async=false

Omx Scaling

With the omxscaler you could do down-scaling and up-scaling of any video source.

Up-scaling the QVGA video test pattern to VGA

gst-launch-1.0 videotestsrc is-live=true num-buffers=1000 ! 'video/x-raw,format=(string)NV12,width=320,height=240,framerate=(fraction)60/1' ! omxscaler  \
! 'video/x-raw,format=(string)YUY2,width=640,height=480,framerate=(fraction)60/1' ! perf print-arm-load=true ! fakesink silent=false -v

Down-scaling the v4l2src captured video to VGA

gst-launch-1.0 v4l2src io-mode=3 num-buffers=100 ! 'video/x-raw,format=(string)NV12,width=1280,height=720,framerate=(fraction)60/1' ! omxbufferalloc num-buffers=12 ! \
omxscaler ! 'video/x-raw,format=(string)YUY2,width=640,height=480,framerate=(fraction)60/1' ! perf print-arm-load=true ! fakesink silent=false -v

V4l2src video capture

RidgeRun has created some patches in order to have the gst-1.0 v4l2src plugin working in the DM81xx platforms. In this wiki Gst-1.0_v4l2src_in_DM81xx you could find more information about the changes done to get it work. Here are 2 useful examples using v4l2src:

V4l2 Capture and H264 encoded UDP streaming

These instructions show how to do video streaming over the network, a video will be captured on the board and viewed on the host. These pipelines use the port that you configure to send the packets. To configure the port and the host ip to send the streaming you have to set the variables port=$PORT and host=$HOST to your own).

Server: DM81xx

Set the variables HOST and PORT to your own, for example:

HOST=10.251.101.43
PORT=3001

And run the pipeline:

gst-launch-1.0 v4l2src io-mode=3 device=/dev/video0 ! 'video/x-raw,format =(string)NV12,width=1280,height=720,framerate=(fraction)60/1' ! perf print-arm-load=true ! omxbufferalloc num-buffers=12 ! \
omxh264enc i-period=30 idr-period=30 ! mpegtsmux ! udpsink host=$HOST port=$PORT sync=false async=false

Client: Ubuntu PC

Set the same port configured in the server:

PORT=3001

And run the pipeline:

gst-launch-1.0 udpsrc port=$PORT ! tsdemux ! h264parse ! avdec_h264 ! xvimagesink sync=false async=false

V4l2 Capture, H264 encoding and mp4 recording

With this example you could create a mp4 file recording from a camera or any device that provides you video. This pipeline uses the omxh264enc with its i-period and idr-period properties set to 10 in order to keep a good video quality when it is decode by another pipeline or software.

gst-launch-1.0 v4l2src io-mode=3 device=/dev/video0 num-buffers=1000 ! 'video/x-raw,format=(string)NV12,width=1280,height=720,framerate=(fraction)60/1' ! perf print-arm-load=true ! \
 omxbufferalloc num-buffers=12 ! omxh264enc i-period=10 idr-period=10 ! queue ! rrh264parser single-nalu=true ! mp4mux dts-method=0 ! filesink location=test_v4l2src_1.0.mp4

Omx H264 decoding

With the omxh264 decoder you are able to decode H264 video streaming or a previously recorder video in order to have raw video to be processed:

Decode H264 video streaming

From the host side we have to generate a test video pattern to send via udp:

Server: Ubuntu PC

Set the variables HOST and PORT to your own, for example:

HOST=10.251.101.120
PORT=3001

And run the pipeline:

gst-launch-1.0 videotestsrc is-live=true ! 'video/x-raw,format=(string)NV12,width=1280,height=720,framerate=(fraction)30/1'  ! x264enc byte-stream=true key-int-max=2 ! \
h264parse ! mpegtsmux ! udpsink host=$HOST port=$PORT sync=false -v

Client: DM81xx

Set the same port configured in the server:

PORT=3001

And run the pipeline:

gst-launch-1.0 udpsrc port=$PORT ! tsdemux ! h264parse ! queue ! omxh264dec ! fakesink silent=false -v

Decode H264 mp4 file

Set the file name to be decoded, for example:

FILE=test_v4l2src_1.0.mp4

And run the pipeline:

gst-launch-1.0 filesrc location=$FILE ! qtdemux ! h264parse ! perf ! queue ! omxh264dec ! fakesink -v

Omx video capture

You have to set the CAPS with the resolution and framerate of your video source, for example:

CAPS='video/x-raw,format=(string)NV12,width=1280,height=720,framerate=(fraction)60/1'

Simple video capture

gst-launch-1.0 omxcamera num-buffers=100 ! $CAPS ! perf print-arm-load=true ! fakesink silent=true -v

Capture and scaling

You have to set the resolution to scale, for example:

SCALECAPS='video/x-raw,format=(string)NV12,width=640,height=480,framerate=(fraction)60/1'

And run the pipeline:

gst-launch-1.0 omxcamera num-buffers=1000 ! $CAPS ! omxscaler ! $SCALECAPS ! perf print-arm-load=true ! fakesink silent=true -v

We could encode the captured and scaled video:

gst-launch-1.0 omxcamera num-buffers=1000 ! $CAPS ! omxscaler ! $SCALECAPS ! perf print-arm-load=true ! videoconvert ! omxh264enc ! fakesink silent=true -v

Omx Capture, H264 encoding and mp4 recording

gst-launch-1.0 omxcamera num-buffers=300 ! 'video/x-raw,format=(string)NV12,width=1280,height=720,framerate=(fraction)60/1' ! perf print-arm-load=true ! \
 omxh264enc i-period=10 idr-period=10 ! queue ! rrh264parser single-nalu=true ! mp4mux dts-method=0 ! filesink location=test_omxcamera_1.0.mp4