In order to get USB cameras (web cams) working on i.MX 51 EVK board running Ubuntu, a few steps must be followed, and they are: Enable USB Camera's drivers on Kernel Test it using Gstreamer or another compatible software (as Cheese) Kernel Driver USB cameras (web cameras) on Linux work over GSPCA driver, to enable this driver you need to go to: ./ltib -c   [*] Configure the kernel     Device Drivers -->          Multimedia Devices -->               [*] Video Capture Adapters -->                    [*] V4L USB Devices -->                         <*> USB Video Class (UVC)                                      [*] UVC input events device support                         <*> GSPCA Based WebCams --> From this point, you need to choose your specific driver. If you don't know, you can select all of those options as a built-in module "<*>" that will work. GSPCA Drivers USB Camera Detection Connect your USB camera to the USB Host port on i.MX 51 EVK board and then type "dmesg", and also check if there is a video0 device using: ubuntu@ubuntu-desktop:~$ ls /dev/video0 /dev/video0 USB Camera Detection Gstreamer Command Line In order to test your USB camera using Gstreamer plugin, use the following command line to perform it: ubuntu@ubuntu-desktop:~$ gst-launch-0.10 v4l2src ! ffmpegcolorspace ! ximagesink and the results: Hi there !!! EOF !

Qt Creator can be a very good IDE in order to develop great QT applications. This IDE does not only helps with syntax highlighting, access to examples and tutorials, but also helps you to configure different toolchains Qt binary versions and target options. First download the binary installer from: For 32 bits: $ wget http://releases.qt-project.org/qtcreator/2.6.2/qt-creator-linux-x86-opensource-2.6.2.bin For 64 bits: $ wget http://releases.qt-project.org/qtcreator/2.6.2/qt-creator-linux-x86_64-opensource-2.6.2.bin execute the binary $ ./qt-creator-linux-x86_64-opensource-2.6.2.bin Follow the Installer GUI and choose a location. Default options should be OK. in my case the installation was done here: $ /home/b35153/qtcreator-2.6.2/bin Open Qt Creator (in my case from command line, use "&" to regain control of the terminal) $./qtcreator & Open Tools -> Options Choose Build & Run  on the menu of the left. and Select the Compilers Tab Here you can add the toolchain GCC compiler of your convenience. It will appear in the "Manual"  section. Now click on Qt Version Tab.  Here you can add the Qmake that you had created with your Qt installation; for example, the Qt5 installation described here: Building QT for i.MX6 It will appear in the Manual section. In my case I have Qmake for PC and Qmake for i.MX6. Now click on Kits Tab Here you can create combinations of Compilers and Qmake, and also specify where do you want the executables to go. In my case here I combined the i.MX6 toolchain and the Qmake for I.MX6 i had created. I did not set up device configuration since the sysroot is already shared to my device via NFS, but you can configure it so the files are sent via ssh to your device. And that's It! Next time you load a project you can choose which Kit you want to work on, and it will be compiled just as you need.

GStreamer has a simple feature to enable tracing, allowing the developer to do basic debugging. These can be done in two ways: Adding the parameter --gst-debug=LIST to the pipeline (a pipeline is a executed gst-launch command) Prepending the environment variable GST_DEBUG=LIST' LIST is a a comma-separated argument, indicating the GStreamer elements to trace. For example, if one needs to trace the sink element      $ GST_DEBUG=*sink*:5 gst-launch playbin2 uri=file:///sample.avi or      $ gst-launch playbin2 uri=file:///sample.avi --gst-debug=*sink*:5 Both commands produces the same log. In case want to trace for than one element, so can simple add the <element>:5, for example      $ GST_DEBUG=mfw_v4lsink:5,vpudec:5 gst-launch playbin2 uri=file:///sample.avi The number 5 indicates the log category, where 5 is the highest (the most verbose log you can get) and 0 produces no output (5=LOG, 4=DEBUG, 3=INFO, 2=WARN, 1=ERROR). Log can be huge in each pipeline run. One way to filter it is using the grep command. Before grepping, one needs to redirect the standard error to the standard output (GStreamer log goes always to stderr), so      $ GST_DEBUG=mfw_v4lsink:5,vpudec:5 gst-launch playbin2 uri=file:///sample.avi 2>&1 | grep <filter string> In case the log needs to be shared, it is important to remove the 'color' of the log, again, one just needs to add the parameter --gst-debug-no-color or prepend the env variable GST_DEBUG_NO_COLOR=1 ----- More shell variables that GStreamer react, can be found here https://developer.gnome.org/gstreamer/0.10/gst-running.html

Overview: This document is written for Freescale customers who have Freescale AC3 release packages (excluded package). (If you did not have the AC3 release package, you can disregard this document.) Freescale OMX Player in Android release supports audio track selection when playing files with multiple audio tracks. However, most customers don't use this enhanced API to select the audio track even if current audio codec is not supported. To avoid a soundless output when partial audio track can be played, this document provides the method to select the available audio track automatically to play. The patch in this document is not included in our current release because it did not match with our track selection rule - play the first track. If you have any idea with this issue, feel free to add comments into this document. Issue description: Software: R13.4-GA or R13.4.1 Android releases Hardware: MX6Dual/Quad SabreSD board Test source: 1.mkv Test Step: 1. Lunch Gallery from main menu. 2. Play the video And you can see the watch the video without any sound Root Reason: The file has 2 audio track DTS & AC3: audio track 1 is DTS and track 2 is AC3. OMX Player will choose the first audio track to play as default audio track, which is DTS audio. However, the software only supports the AC3 audio codec, so it could not set up audio decoder for DTS track. If we choose to play the AC3 track, sounds could be heard. How to fix: The audio track index is set in GMPlayer::LoadParser(). You can get audio format to check whether it is supported by decoder. Please see the patch audio_track_slection.diff

gst-inspect is a tool to to get documentation about GStreamer elements. Pipeline Check installed GST elements gst-inspect | tail -1 Check installed FSL GST elements gst-inspect | grep imx Element documentation gst-inspect <gst element>

There is no Freescale GStreamer element which does the JPEG decoding, so we must rely on a standard one, like 'jpegdec'. In case your Linux system was built using LTIB, in order to have the jpegdec element included on the gst-plugin-good, follow these steps: On the LTIB menuconfig, make sure the following packages are selected: gstreamer-plugins-good libjpeg libpng Remove the configure parameters '--disbale-libpng' and '--disable-jpeg' on the file './dist/lfs-5.1/gst-plugins-good/gst-plugins-good.spec' Rebuild and flash your board (or SD card) again. Image display VSALPHA=1 gst-launch filesrc location=sample.jpeg ! jpegdec ! imagefreeze ! mfw_isink Important: non 8 pixel aligned width and height is treated as not supported format in isink plugin.

Dumping the pipeline elements into a image file # On target, run the pipeline $ export GST_DEBUG_DUMP_DOT_DIR=<folder where dot files are created> $ gst-launch playbin2 uri=file://${avi} $ # Move the .dot files to a host machine (scp, etc) # On Host dot <dot file> -Tpng -o out.png # dot command is part the the graphviz package Querying which elements are being used on a gst-launch command GST_DEBUG=GST_ELEMENT_FACTORY:3 gst-launch playbin2 uri=file://`pwd`/<media file> Interrupting a gst-launch process running in the background kill -INT $PID # where $PID is the process ID Using only SW codecs # Backup and remove $ find /usr/lib/gstreamer-0.10 -name "libmfw*" | grep -v sink | xargs tar cvf /libmfw_gst.tar $ find /usr/lib/gstreamer-0.10 -name "libmfw*" | grep -v sink | xargs rm # Run your pipeline. This time SW codecs are used $ gst-launch playbin2 uri=file://`pwd`/media_file # To 'install' FSL plugins again, just untar the file $ cd / && tar xvf libmfw_gst.tar && cd - # then run your pipeline. This time HW codecs are used $ gst-launch playbin2 uri=file://`pwd`/media_file

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-343528 

All Boards Creating App MP3 OpenEmbedded

Audio transcoding # Transcode the input file into MP3 gst-launch filesrc location=media_file typefind=true ! beepdec ! mfw_mp3encoder ! matroskamux ! filesink location=output_audio_file.mk Audio transcoding + streaming # Transcode the input file into MP3 and stream it # On host, get the transcoded audio data gst-launch udpsrc port=8880 ! <CAPS_FROM_THE_TARGET> ! queue ! ffdec_mp3 ! alsasink # where <CAPS_FROM_THE_TARGET> can be something like 'audio/mpeg, mpegversion=(int)1, layer=(int)3, rate=(int)44100, channels=(int)2' # run the pipeline and check the caps gst-launch filesrc location=media_file typefind=true ! queue ! beepdec ! mfw_mp3encoder ! udpsink host=10.112.103.77 port=8880 -v Video Transcoding* # Transcode the input file into AVC (H-264) gst-launch filesrc location=media_file typefind=true ! aiurdemux name=demux ! queue ! vpudec ! vpuenc codec=avc ! matroskamux name=mux ! filesink location=output_media_file.mk Video Transcoding + scaling* # Transcode the input file into AVC (H264) and rescale video to 480p gst-launch filesrc location=media_file typefind=true ! aiurdemux name=demux ! queue ! vpudec ! mfw_ipucsc ! 'video/x-raw-yuv, width=(int)720, height=(int)480' ! vpuenc codec=avc ! matroskamux name=mux ! filesink location=output_media_file.mk Video transcoding + scaling + streaming* # NOTE: Run the pipelines in the presented order # On host, get the transcoded+scaled video data $ gst-launch udpsrc port=8888 ! <CAPS_FROM_THE_TARGET> ! queue ! ffdec_h264 ! xvimagesink # On target, run the pipeline and check the caps gst-launch filesrc location=media_file typefind=true ! aiurdemux name=demux ! queue ! vpudec ! mfw_ipucsc ! 'video/x-raw-yuv, width=(int)720, height=(int)480' ! vpuenc codec=avc ! udpsink host=$HOST_IP port=8888 -v * There is a limit for the number of pipelines which can be run simultaneously, for high resolution input files, at most two for 1080p and four for 720p.

This document describes the i.MX 8MM EVK mini-SAS connectors features on Linux and Android use cases, covering the supported daughter cards, the process to change Device Tree (DTS) files or Boot images, and enable these different display options on the board.

This is the prototype solution to enable second display showing different things on JB4.2.2 SabreSD. Make use of Class Presentation provided by android to be embedded into Status bar. When unlock the screen, the Presentation will show on second display. Now, the solution requires one .mp4 video placed in root sdcard. Of course, you may change it to show anything. The attached Files are a layout xml file, a patch and a recorded video. The layout file should be put into android/frameworks/base/packages/SystemUI/res/layout/ folder. The patch should be applied to frameworks/base.git. The recorded video shows the dual display demo as a reference.

gst-launch is the tool to execute GStreamer pipelines. Task Pipeline Looking at caps gst-launch -v  <gst elements> Enable log gst-launch --gst-debug=<element>:<level> gst-launch --gst-debug=videotestsrc:5 videotestsrc ! filesink location=/dev/null