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Some i.MX25 customers reported an issue for the GPT timer, when using 120MHz (240MHz UPLL divided 2) clock source as the GPT per_clk, the timer will not be increased all the time in free-run mode. If using 66.5MHz IPG clock and 133MHz PER clock as the clock source, there are no such issue. There are 4 test cases in the attached test code. Case 0: in CCM_MCR, set bit 5 as 0 for 133MHz HCLK as the gpt_per_clk source; in GPT_CR bit[8:6], set 0b001 ipg_clk (66.5MHz). There is no issue, the GPT counter is fixed at 4 between old_cnt and new_cnt. Case 1: in CCM_MCR, set bit 5 as 0 for 133MHz HCLK as the gpt_per_clk source; in GPT_CR bit[8:6], set 0b010 ipg_clk_highfreq (133MHz). There is no issue, the GPT counter is fixed at 8 between old_cnt and new_cnt. Case 2: in CCM_MCR, set bit 5 as 1 for 240MHz UPLL divided by 2 as the gpt_per_clk source; in GPT_CR bit[8:6], set 0b001 ipg_clk (60MHz). There is no issue, the GPT counter is fixed at 4 between old_cnt and new_cnt. Case 3: in CCM_MCR, set bit 5 as 0 for 240MHz UPLL divided by 2 as the gpt_per_clk source; in GPT_CR bit[8:6], set 0b010 ipg_clk_highfreq (120MHz). There is issue, the GPT counter is not a fixed value between old_cnt and new_cnt, and sometimes it will be negative. Count 9874: 4 old_cnt: 0x188849dc new_cnt: 0x188849e0 Count 9877: 12 old_cnt: 0x18918400 new_cnt: 0x1891840c Count 9915: 4 old_cnt: 0x189aea90 new_cnt: 0x189aea94 Count 9937: -12 old_cnt: 0x18a42458 new_cnt: 0x18a4244c Count 9967: 4 old_cnt: 0x18adb17c new_cnt: 0x18adb180 In fact, it is not an issue, when using UPLL as the GPT clock source, the maxim frequency should be 60MHz. That's why all other three test case is OK and it only failed on this case.

This is a generic script which flashes a Linux System (U-boot, uImage and root filesystem) into a SD card. Steps: 1. Download the script into a Linux system 2. Make the script executable (chmod +x mk_mx_sd) 3. Run it with '-H' to know its usage. 4. Run the script with real parameters, specifying the paths for U-boot, uImage and the root filesystem as seen above 5. Plug the SD into your target, boot the board and change the corresponding U-boot variables $ IMAGE=/data/BSP/L2.6.35_11.09.01_ER/L2.6.35_11.09.01_ER_images_MX5X $ ./mk_mx_sd -d /dev/sdc \ -u $IMAGE/u-boot-mx53-loco.bin \ -k $IMAGE/uImage \ -r $IMAGE/rootfs 6. In case you only want to flash a single binary (like U-boot), just specify the U-boot parameter (-u)

When flashing a Linux System on a SD card using the script mk_mx28_sd on a Ubuntu 12.04 host, one needs to modify it so partitions are created correctly. Just follow these steps on the console: $ cd $SDK/L2.6.35_10.12.01_SDK_scripts $ cat > first_partition_sector.patch << EOF diff -Naur a/mk_mx28_sd b/mk_mx28_sd --- a/mk_mx28_sd 2010-10-06 09:47:42.000000000 -0500 +++ b/mk_mx28_sd 2012-11-30 13:38:34.508199154 -0600 @@ -178,7 +178,7 @@ n p 1 -1 +2048 +32M t b EOF $ patch -p1 < first_partition_sector.patch then, you can run the mk_mx28_sd command again with the device as parameter $ cd $LIB $ export PATH=$PATH:$SDK/L2.6.35_10.12.01_SDK_scripts $ mk_mx28_sd /dev/$SDX

(DEPRECATED. Please check this document for Real Time Streaming) A server can be streaming video and a client, in this case a i.MX6 target, is receiving and decoding it. For example, a server with GStreamer and a web camera connected, can be streaming with the following command: $ # Pipeline 1 $ gst-launch v4l2src ! 'video/x-raw-yuv, format=(fourcc)I420, width=(int)1280, height=(int)800' ! ffenc_mpeg4 ! tcpserversink host=$CLIENT_IP port=$PORT and on the target, the client receives, decodes and display with $ # Pipeline 2 $ gst-launch tcpclientsrc host=$SERVER_IP port=$PORT ! 'video/mpeg, width=(int)1280, height=(int)800, framerate=(fraction)10/1, mpegversion=(int)4, systemstream=(boolean)false' ! vpudec ! mfw_isink The filter caps between the tcpclientsrc and the decoder (vpudec) depend on the sink caps coming from the server encoder (ffenc_mpeg4), so these may change depending on your needs. Running the above pipelines require the environment variables SERVER_IP, CLIENT_IP and PORT. In case you want the i.MX6 to act as a server, just change the video source (either mfw_v4lsrc of v4l2src) and the encoder (vpuenc), so $ # Pipeline 3 $ gst-launch v4l2src ! 'video/x-raw-yuv, format=(fourcc)I420, width=(int)640, height=(int)480, interlaced=(boolean)false, framerate=(fraction)10/1' ! vpuenc ! tcpserversink host=$CLIENT_IP port=$PORT For testing purposes, set SERVER_IP=127.0.0.1, CLIENT_IP=127.0.0.1 and PORT=500, and run pipeline 3 and 2 in two different consoles. Check with 'top' the CPU usage and see that VPU is actually doing most of the work.

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

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.

Multiple-Overlay (or Multi-Overlay) means several video playbacks on a single screen. In case multiple screens are needed, check the dual-display case GStreamer i.MX6 Multi-Display $ export VSALPHA=1 $ SAMPLE1=sample1.avi; SAMPLE2=sample2.avi; SAMPLE3=sample3.avi; SAMPLE4=sample4.avi; $ WIDTH=320; HEIGHT=240; SEP=20 Four displays (2x2) $gst-launch \ playbin2 uri=file://`pwd`/$SAMPLE1 video-sink="mfw_isink axis-top=0 axis-left=0 disp-width=$WIDTH disp-height=$HEIGHT" \ playbin2 uri=file://`pwd`/$SAMPLE2 video-sink="mfw_isink axis-top=0 axis-left=`expr $WIDTH + $SEP` disp-width=$WIDTH disp-height=$HEIGHT" \ playbin2 uri=file://`pwd`/$SAMPLE3 video-sink="mfw_isink axis-top=`expr $HEIGHT + $SEP` axis-left=0 disp-width=$WIDTH disp-height=$HEIGHT" \ playbin2 uri=file://`pwd`/$SAMPLE4 video-sink="mfw_isink axis-top=`expr $HEIGHT + $SEP` axis-left=`expr $WIDTH + $SEP` disp-width=$WIDTH disp-height=$HEIGHT" Basic rotation, (2 x 1, normal and inverted) gst-launch \ playbin2 uri=file://`pwd`/$SAMPLE1 video-sink="mfw_isink axis-top=0 axis-left=0 disp-width=$WIDTH disp-height=$HEIGHT rotation=0" \ playbin2 uri=file://`pwd`/$SAMPLE2 video-sink="mfw_isink axis-top=`expr $HEIGHT + $SEP` axis-left=0 disp-width=$WIDTH disp-height=$HEIGHT rotation=3"

i.MX6DQ HDMI dongle board uses BCM4330 which is SDIO interface as wireless module. When we try to run Ubuntu oneiric on HDMI dongle board, after correctly insmod bcm4330.ko, we found Ubuntu NetworkManger can't recognize this interface: the /var/log/syslog shows the following error: Jan 1 00:01:08 linaro-ubuntu-desktop NetworkManager[4787]: SCPlugin-Ifupdown: devices added (path: /sys/devices/virtual/net/wlan0, iface: wlan0) Jan 1 00:01:08 linaro-ubuntu-desktop NetworkManager[4787]: SCPlugin-Ifupdown: device added (path: /sys/devices/virtual/net/wlan0, iface: wlan0): no ifupdown configuration found. Jan 1 00:01:08 linaro-ubuntu-desktop NetworkManager[4787]: <warn> /sys/devices/virtual/net/wlan0: couldn't determine device driver; ignoring... After using Google search, we found /sys/devices/virtual/net/wlan0 directory dose not has directory "device", this "device" directory should be exist at network interface, without it, NetworkManager will get error "couldn't determine device driver; ignoring...", the "device" is just this network interface come from, and it should link to the real device under one hardware bus. While the bcm4330 Linux driver from Broadcom does not setup network interface real "device" so we need add this real "device" before the driver registers a network interface. Refer to the attached diff file for this modification

In some cases it is desired to directly have progressive content available from a TV-IN interface through the V4L2 capture device. In the BSP, HW accelerated de-interlacing is only supported in the V4L2 output stream. Below is a patch created against a rather old BSP version that adds support for de-interlaced V4L2 capture. The patch might need to be adapted to newer BSPs, However, the logic and functionality is there and should shorten the development time. This patch adds another input device to the V4L2 framework that can be selected to perform the deinterlacing on the way to memory. The selection is done by passing the index “2” as an argument to the VIDIOC_S_INPUT V4L2 ioctl. Attached is also a modified the tvin unit test to give an example of how to use the new driver. An example sequence for running the test is as follows: modprobe mxc_v4l2_capture ./mxc_v4l2_tvin_vdi.out -ow 720 -oh 480 -ol 10 -ot 20 -f YU12 Some key things to note: This driver does not support resize or color space conversion on the way to memory. The requested format and size should match what can be provided directly by the sensor. The driver was tested on a Sabre AI Rev A board running Linux 12.02. This code is not an official delivery and as such no guarantee of support for this code is provided by Freescale.

Here is an example for i.MX28 EVK board to support SPI NOR boot in uboot, kernel and MFGTool. Attached files are the patches to support SPI NOR flash on i.MX28 EVK bord based on L2.6.35 ER11.09.01 BSP. It was verified on Spansion s25fl256s SPI NOR. "ER11.09.01_uboot_imx28_spi_nor.patch" is the Uboot patch. "ER11.09.01_kernel_imx28_spi_nor.patch" is the kernel patch. "ucl.xml" is the updated MFGTool config file, please update it to "Mfgtools-Rel\Profiles\MX28 Linux Update\OS Firmware\ucl.xml". The uboot boot paramters for SPI: setenv bootargs_base 'setenv bootargs console=ttyAM0,115200' setenv loadaddr 0x42000000 setenv bootargs_spi 'setenv bootargs ${bootargs} root=/dev/mtdblock2 rootfstype=jffs2 rootwait rw ip=none' setenv bootcmd_spi 'run bootargs_base bootargs_spi;sf probe 2:0; sf read ${loadaddr} 0x100000 0x300000;bootm' setenv bootcmd 'run bootcmd_spi' saveenv To boot the board from SPI NOR s25fl256s, the 4KB page region of the NOR should be put to top, the last 128KB of the NOR address space. The uboot.sb is about 220KB, it can't be put to 4KB and 64KB combined region. The IMX28 boot ROM can only handle simple page size for boot. All 4KB page region or all 64KB page region are both OK for boot, but combined region can't boot. For default, the s25fl256s NOR's 128KB 4KB page size region is at the bottom of the NOR, we should update the OTP to set this region to TOP, in Uboot, we run the followed command to burn the OTP: MX28 U-Boot -> sf probe 2:0 MX28 U-Boot -> sf set_config_reg 0x04 To boot the i.MX28 EVK board from SPI2 NOR flash, the BM3~0 should be 0010. In this example, we only used the JFFS2 file system. To support the UBIFS, there is a known issue, that the UBIFS will use vmalloc to alloc memory, and if SPI driver used the DMA, kernel will halt with error "kernel BUG at arch/arm/mm/dma-mapping.c:409!". For 11.09.01 BSP, the default MFGTool rootfs "initramfs.cpio.gz" will be bigger than 4MB, but in i.MX28 bootlets code, the BSP only set ramdisk to 4MB, so we need modify this limitation for MFGTool. Use command "./ltib -p imx-bootlets -m prep" to get the bootlets code, modify "ltib/rpm/BUILD/imx-bootlets-src-11.09.01/linux_prep/core/setup.c", function setup_initrd_tag(), change from "params->u.initrd.size = 0x00400000;" to "params->u.initrd.size = 0x00500000;". Modify "ltib/rpm/BUILD/imx-bootlets-src-11.09.01/updater.bd" and "updater_ivt.bd", change from "load 0.b > 0x40800000..0x40c00000;" to "load 0.b > 0x40800000..0x40d00000;". Now the MFGTool rootfs size can be 5MB. 2013-05-09: Updated hardware rework: On iMX28 EVK board, rework J89 as followed and mount R320,R321,R322 and C178. MX28 U49 Pin1 /CS <-> NOR Pin7 CS# MX28 U49 Pin2 D0 <-> NOR Pin8 SI/IO1 MX28 U49 Pin5 DIO <-> NOR Pin15 SI/IO0 MX28 U49 Pin6 CLK<-> NOR pin 16 SCK. MX28 U49 Pin8 VCC <-> NOR Pin2 VCC MX28 U49 Pin4 GND <-> NOR Pin10 VSS MX28 U49 Pin3 /WP <-> NOR Pin9 WP MX28 U49 Pin7 /Hold <-> NOR Pin pin1 hold Software reset issue for 32MB SPI NOR: For 32MB SPI NOR, after booted into kernel, the kernel driver will set SPI NOR to 4 bytes address mode, but for iMX28 SPI boot, it can only boot with 3 bytes address mode, if reset the iMX28 board but SPI NOR was not reset, it will fail to reboot. Hardware solution: when iMX28 was reboot, reset the SPI NOR too, the SPI NOR will work in 3 bytes address mode as default. Software solution: In kernel SPI NOR driver, always switch SPI NOR to 3 bytes address mode after each SPI NOR access, and switch to 4 bytes address mode before each access. There is no such issue if the SPI NOR size is less than 32MB.

The original implementation is from Frias Renato for Sabreauto board. How to define the booting time? The booting time we defined here is from the board be powered up to the main application working and main application be showed directly to the end user, for example: for the media play purpose board, the booting time count to the first video frame be shown on the screen. For minimizing the booting time, some methods be tried. Optimizing for performance. Remove unnecessary modules at boot time. Start main application at the first time after the kernel be boot up. Optimizing for performance: U-Boot: 1:Enable MMU and L2-Cache. 2:Optimizing memset and memcpy. 3:Implementation of SDMA, accelerate copying data from NOR flash to memory. 4:Implementation of uSDHC’s ADMA, improve performance for SD card read. Kernel: 1:Optimizing _memcpy_fromio function at arch/arm/kernel/io.c Remove unnecessary modules: U-Boot: 1: Disable uart output at u-boot procedure and add quiet parameter to Kernel boot. 2: Remove boot up delay at u-boot. 3: Disable I2C, SPI, SPLASH_SCREEN at u-boot. Kernel: Below removing unnecessary modules just for Sabresd board boot up through SD card and MIPI camera overlay on LVDS screen application, for other special board and special board usage application please don’t use below directly. 1: Modify arch/arm/mach-mx6/board-mx6q_sabresd.c just keep necessary module initialization at mx6_sabresd_board_init : iomux configuration, uart0, voda, ipu, ldb, v4l2, mipi-csi, i2c1, uSDHC1, pwm0, dvfs, mipi camera clock. 2: Update Linux kernel configuration file. Try to just keep necessary module and configuration to keep minim size. Build necessary modules from external to Kernel itself. Create uImage from Image instead of zImage to reduce Kernel self extraction time. Use ext4 file system on SD card to accelerate rootfs mounting. Notice: Kernel configuration remove NETWORK support, it includes Unix Domain Socket, the udev mechanism need it, so this kernel configuration can't support rootfs udev dynamic /dev/ nodes and all /dev/ nodes must be created before boot up at rootfs. Start main application at the first time after the kernel boots up. As normal boot up procedure, the init process will handle sysinit script firstly, this script will do some initialization and preparation for most of the user process, But this script normally will be executed for about 1~5 seconds, so now try do main application before the sysinit, while the necessary preparation of main application will be handle by this application internally. See below example for MIPI camera overly on LVDS screen: /etc/inittab ::once:/unit_tests/mxc_v4l2_overlay.out -iw 640 -ih 480 -it 0 -il 0 -ow 1024 -oh 768 -ot 0 -ol 0 -r 0 -t -1 -d 0 -fg -fr 30 ::once:/etc/rc.d/rcS ::once:/sbin/getty -L ttymxc0 115200 vt100 # GENERIC_SERIAL Test result of fast boot on Sabresd board for MIPI camera overly on LVDS screen: The main application be executed from the board be powered up is about 958ms. Running Bootloader [0.356417 0.356417] [ 0.046637] _regulator_get: get() with no identifier [ 0.958425 0.602008] starting pid 21, tty '': '/unit_tests/mxc_v4l2_overlay.out -iw 640 -ih 480 -it 0 -il 0 -ow 1024 -oh 768 -ot 0 -ol 0 -r 0 -t -^@ [0.969609 0.011184] starting pid 22, tty '': '/etc/rc.d/rcS' [0.973368 0.003759] g_display_width = 1024, g_display_height = 768 [0.977540 0.004172] g_display_top = 0, g_display_left = 0 [0.980927 0.003387] starting pid 23, tty '': '/sbin/getty -L ttymxc0 115200 vt100 ' [1.048454 0.067527] Mounting /proc and /sys [1.089526 0.041072] Setting the hostname to freescale [1.116635 0.027109] Mounting filesystems [1.527320 0.410685] sensor chip is ov5640_mipi_camera [1.530627 0.003307] sensor frame size is 640x480 [1.533482 0.002855] sensor frame format is UYVY [1.640221 0.106739] frame_rate is 30 [1.642249 0.002028] [1.642270 0.000021] frame buffer width 0, height 0, bytesperline 0 [1.989728 0.347458] [1.990761 0.001033] arm-none-linux-gnueabi-gcc (Freescale MAD -- Linaro 2011.07 -- Built at 2011/08/10 09:20) 4.6.2 20110630 (prerelease) [2.001161 0.010400] root filesystem built on Tue, 11 Sep 2012 11:43:24 +0800 [2.006249 0.005088] Freescale Semiconductor, Inc. [2.009394 0.003145] [2.009531 0.000137] freescale login: Please see below fast boot video. I also attached sample code for U-boot and kernel for your reference. Patch code based on L3.0.35_12.09.01_GA.

In this article, some experiments are done to verify the capability of i.MX6DQ on video playback under different VPU clocks. 1. Preparation Board: i.MX6DQ SD Bitstream: 1080p sunflower with 40Mbps, it is considered as the toughest H264 clip. The original clip is copied 20 times to generate a new raw video (repeat 20 times of sun-flower clip) and then encapsulate into a mp4 container. This is to remove and minimize the influence of startup workload of gstreamer compared to vpu unit test. Kernels: Generate different kernel with different VPU clock setting: 270MHz, 298MHz, 329MHz, 352MHz, 382MHz. test setting: 1080p content decoding and display with 1080p device. (no resize) 2. Test command for VPU unit test and Gstreamer The tiled format video playback is faster than NV12 format, so in below experiment, we choose tiled format during video playback. Unit test command: (we set the frame rate -a 70, higher than 1080p 60fps HDMI refresh rate) /unit_tests/mxc_vpu_test.out -D "-i /media/65a78bbd-1608-4d49-bca8-4e009cafac5e/sunflower_2B_2ref_WP_40Mbps.264 -f 2 -y 1 -a 70" Gstreamer command: (free run to get the highest playback speed) gst-launch filesrc location=/media/65a78bbd-1608-4d49-bca8-4e009cafac5e/sunflower_2B_2ref_WP_40Mbps.mp4 typefind=true ! aiurdemux ! vpudec framedrop=false ! queue max-size-buffers=3 ! mfw_v4lsink sync=false 3. Video playback framerate measurement During test, we enter command "echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor" to make sure the CPU always work at highest frequency, so that it can respond to any interrupt quickly. For each testing point with different VPU clock, we do 5 rounds of tests. The max and min values are removed, and the remaining 3 data are averaged to get the final playback framerate. #1 #2 #3 #4 #5 Min Max Avg Dec Playback Dec Playback Dec Playback Dec Playback Dec Playback Playback Playback Playback 270M unit test 57.8 57.3 57.81 57.04 57.78 57.3 57.87 56.15 57.91 55.4 55.4 57.3 56.83 GST 53.76 54.163 54.136 54.273 53.659 53.659 54.273 54.01967 298M unit test 60.97 58.37 60.98 58.55 60.97 57.8 60.94 58.07 60.98 58.65 57.8 58.65 58.33 GST 56.755 49.144 53.271 56.159 56.665 49.144 56.755 55.365 329M unit test 63.8 59.52 63.92 52.63 63.8 58.1 63.82 58.26 63.78 59.34 52.63 59.52 58.56667 GST 57.815 55.857 56.862 58.637 56.703 55.857 58.637 57.12667 352M unit test 65.79 59.63 65.78 59.68 65.78 59.65 66.16 49.21 65.93 57.67 49.21 59.68 58.98333 GST 58.668 59.103 56.419 58.08 58.312 56.419 59.103 58.35333 382M unit test 64.34 56.58 67.8 58.73 67.75 59.68 67.81 59.36 67.77 59.76 56.58 59.76 59.25667 GST 59.753 58.893 58.972 58.273 59.238 58.273 59.753 59.03433 Note: Dec column means the vpu decoding fps, while Playback column means overall playback fps. Some explanation: Why does the Gstreamer performance data still improve while unit test is more flat? On Gstreamer, there is a vpu wrapper which is used to make the vpu api more intuitive to be called. So at first, the overall GST playback performance is constrained by vpu (vpu dec 57.8 fps). And finally, as vpu decoding performance goes to higher than 60fps when vpu clock increases, the constraint becomes the display refresh rate 60fps. The video display overhead of Gstreamer is only about 1 fps, similar to unit test. Based on the test result, we can see that for 352MHz, the overall 1080p video playback on 1080p display can reach ~60fps. Or if time sharing by two pipelines with two displays, we can do 2 x 1080p @ 30fps video playback. However, this experiment is valid for 1080p video playback on 1080p display. If for interlaced clip and display with size not same as 1080p, the overall playback performance is limited by some postprocessing like de-interlacing and resize.

Multiple-Display means video playback on multiple screens. In case playback needs to be in a unique screen, the mfw_isink element must be used and some pipelines examples can be found on this link: GStreamer iMX6 Multi-Overlay. Number of Displays Display type Kernel parameters Pipelines # Set these shells variables before running the pipelines alias gl=gst-launch SINK_1="\"mfw_v4lsink device=/dev/video17\"" SINK_2="\"mfw_v4lsink device=/dev/video18\"" SINK_3="\"mfw_v4lsink device=/dev/video20\"" media1=file:///root/media1 media2=file:///root/media2 media3=file:///root/media3 2 hdmi + lvds video=mxcfb0:dev=hdmi,1920x1080M@60,if=RGB24 video=mxcfb1:dev=ldb,LDB-XGA,if=RGB666 gl playbin2 uri=$media1 video-sink=$SINK_1 playbin2 uri=$media2 video-sink=$SINK_2 2 lvds + lvds video=mxcfb0:dev=ldb,LDB-XGA,if=RGB666 video=mxcfb1:dev=ldb,LDB-XGA,if=RGB666 gl playbin2 uri=$media1 video-sink=$SINK_1 playbin2 uri=$media2 video-sink=$SINK_2 2 lcd + lvds video=mxcfb0:dev=lcd,800x480M@55,if=RGB565 video=mxcfb1:dev=ldb,LDB-XGA,if=RGB666 gl playbin2 uri=$media1 video-sink=$SINK_1 playbin2 uri=$media2 video-sink=$SINK_2 3 hdmi + lvds + lvds video=mxcfb0:dev=hdmi,1920x1080M@60,if=RGB24 video=mxcfb1:dev=ldb,LDB-XGA,if=RGB6 video=mxcfb2:dev=ldb,LDB-XGA,if=RGB666 gl playbin2 uri=$media1 video-sink=$SINK_1 playbin2 uri=$media2 video-sink=$SINK_2 playbin2 uri=$media3 video-sink=$SINK_3

Audio, from a file gst-launch filesrc location=test.wav ! wavparse ! mfw_mp3encoder ! filesink location=output.mp3 Audio Recording gst-launch alsasrc num-buffers=$NUMBER blocksize=$SIZE ! mfw_mp3encoder ! filesink location=output.mp3 # where # duration = $NUMBER*$SIZE*8 / (samplerate *channel *bitwidth) # Example: 60 seconds recording # gst-launch alsasrc num-buffers=240 blocksize=44100 ! mfw_mp3encoder ! filesink location=output.mp3 # # To verify that is correct, do a normal audio playback gst-launch filesrc location=output.mp3 typefind=true ! beepdec ! audioconvert ! 'audio/x-raw-int,channels=2' ! alsasink Video, from a test source gst-launch videotestsrc ! queue ! vpuenc ! matroskamux ! filesink location=./test.avi Video, from a file gst-launch filesrc location=sample.yuv blocksize=$BLOCK_SIZE ! 'video/x-raw-yuv,format=(fourcc)I420, width=$WIDTH, height=$HEIGHT, framerate=(fraction)30/1' ! vpuenc codec=$CODEC ! matroskamux ! filesink location=output.mkv sync=false # where # BLOCK_SIZE = WIDTH * HEIGHT * 1.5 # CODEC = 0(MPEG4), 5(H263), 6(H264) or 12(MJPG). # # For example, encoding a CIF raw file gst-launch filesrc location=sample.yuv blocksize=152064 ! 'video/x-raw-yuv,format=(fourcc)I420, width=352, height=288, framerate=(fraction)30/1' ! vpuenc codec=0 ! matroskamux ! filesink location=sample.mkv sync=false Video, from Web camera # when the web cam is connected, the device node /dev/video0 should be present. In order to test the camera, without encoding gst-launch v4l2src ! mfw_v4lsink # in recording, run: # gst-launch v4l2src num-buffers=-1 ! queue max-size-buffers=2 ! vpuenc codec=0 ! matroskamux ! filesink location=output.mkv sync=false # # where sync=false indicates filesink to to use a clock sync # # In case a specific width/height is needed, just add the filter caps gst-launch v4l2src num-buffers=-1 ! 'video/x-raw-yuv,format=(fourcc)I420, width=352, height=288, framerate=(fraction)30/1' ! queue ! vpuenc codec=0 ! matroskamux ! filesink location=output.mkv sync=false # # In case you want to see in the screen what the camera is capturing, add a tee element # gst-launch v4l2src num-buffers=-1 ! tee name=t ! queue ! mfw_v4lsink t. ! queue ! vpuenc codec=0 ! matroskamux ! filesink location=output.mkv sync=false Video, from Parallel/MIPI camera # The camera driver needs to be loaded before executing the pipeline, refer to the BSP document to see which driver to load # MIPI (J5 port): modprobe ov5640_camera_mipi modprobe mxc_v4l2_capture # Parallel (J9 port): modprobe ov5642_camera modprobe mxc_v4l2_capture gst-launch mfw_v4lsrc ! queue ! vpuenc codec=0 ! matroskamux ! filesink location=output.mkv sync=false # Do a 'gst-inspect mfw_v4lsrc' or 'gst-inspect vpuenc' to see other possible settings (resolution, fps, codec, etc.)

Video, bad performance gst-launch filesrc location=test.mp4 typefind=true ! aiurdemux ! vpudec ! mfw_v4lsink Video, better performance gst-launch filesrc location=sample.mp4 typefind=true ! aiurdemux ! queue max-size-time=0 ! vpudec ! mfw_v4lsink # typefind=true allows to 'type find' the source file before negotiating # max-size-time=0 indicates to ignore possible blocking issues # In case of ASF files gst-launch filesrc location=sample.asf typefind=true ! aiurdemux ! queue max-size-time=0 ! mfw_wmvdecoder ! mfw_v4lsink Audio gst-launch filesrc location=sample.mp3 typefind=true ! beepdec ! audioconvert ! 'audio/x-raw-int, channels=2' ! alsasink Audio with visualization gst-launch filesrc location=sample.mp3 typefind=true ! beepdec ! tee name=t ! queue ! audioconvert ! 'audio/x-raw-int, channels=2' ! alsasink t. ! queue ! audioconvert ! goom ! autovideoconvert ! autovideosink Video/Audio long version gst-launch filesrc location=sample.avi typefind=true ! aiurdemux name=demux demux. ! queue max-size-buffers=0 max-size-time=0 ! vpudec ! mfw_v4lsink demux. ! queue max-size-buffers=0 max-size-time=0 ! beepdec ! audioconvert ! 'audio/x-raw-int, channels=2' ! alsasink # queue properties, max-size-buffers=0 and max-size-time=0, allows a smoother playback; type 'gst-inspect queue' for more info VA short version gplay sample.avi VA short version gst-launch playbin2 uri=file://<full path to sample file>

Header 1 Header 2 Video rendering gst-launch videotestsrc ! mfw_v4lsink Audio rendering gst-launch audiotestsrc ! alsasink WAV Audio rendering gst-launch filesrc location=test.wav ! wavparse ! alsasink Video rendering selecting caps gst-launch videotestsrc ! capsfilter name='video/x-raw-yuv,format=(fourcc)I420' ! mfw_v4lsink gst-launch videotestsrc ! 'video/x-raw-yuv,format=(fourcc)I420' ! mfw_v4lsink

i.MX Processors Knowledge Base

i.MX Processors Knowledge Base

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