I'm trying to use a jpg-File as a virtual webcam for Skype (or similar). The image file is reloading every few seconds and the Pipeline should also transmit always the newest image.
I started creating a Pipeline like this
gst-launch filesrc location=~/image.jpg ! jpegdec ! ffmpegcolorspace ! freeze ! v4l2sink device=/dev/video2
but it only streams the first image and ignores the newer versions of the image file. I read something about concat and dynamically changing the Pipeline but I couldn't get this working for me.
Could you give me any hints on how to get this working?
Dynamic refresh the input file is NOT possible (at least with filesrc).
Besides, your sample use freeze, which will prevent the image change.
One possible method is using multifilesrc and videorate instead.
multifilesrc can read many files (with a provided pattern similar to scanf/printf), and videorate can control the speed.
For example, you create 100 images with format image0000.jpg, image0001.jpg, ..., image0100.jpg. Then play them continuously, with each image in 1 second:
gst-launch multifilesrc location=~/image%04d.jpg start-index=0 stop-index=100 loop=true caps="image/jpeg,framerate=\(fraction\)1/1" ! jpegdec ! ffmpegcolorspace ! videorate ! v4l2sink device=/dev/video2
Changing the number of image at stop-index=100, and change speed at caps="image/jpeg,framerate=\(fraction\)1/1"
For more information about these elements, refer to their documents at gstreamer.freedesktop.org/documentation/plugins.html
EDIT: Look like you use GStreamer 0.10, not 1.x
In this case, please refer to old documents multifilesrc and videorate
You can use a general file name with multifilesrc if you add some parameter adjustments and pair it with an identity on a delay. It's a bit fragile but it'll do fine for a temporary one-off program as long as you keep your input images the same dimensions and format.
gst-launch-1.0 multifilesrc loop=true start-index=0 stop-index=0 location=/tmp/whatever ! decodebin ! identity sleep-time=1000000 ! videoconvert ! v4l2sink
Related
I'm trying to reduce the frame rate of a branch in my pipeline using videorate The real application is using a c project and is running on a Jetson Xavier AGX but I can demonstrate with these launch scripts.
The goal is to get a pipeline like this to work
nvv4l2camerasrc device=/dev/v4l/by-path/platform-15c10000.vi-video-index0
! video/x-raw(memory:NVMM),width=1920,height=1080,framerate=30/1,format=UYVY,interlace-mode=progressive
! videorate drop-only=true ! video/x-raw(memory:NVMM),framerate=10/1
! filesink location=test.I420
This launches ok and a test.I420 file is created but it seems no data is written to it.
Adding a nvvidconv element to convert the buffers into CPU memory (I think this is what its doing?) works. Be careful this creates a massive file very quickly.
nvv4l2camerasrc device=/dev/v4l/by-path/platform-15c10000.vi-video-index0
! video/x-raw(memory:NVMM),width=3840,height=2160,framerate=30/1,format=UYVY,interlace-mode=progressive
! nvvidconv ! video/x-raw
! videorate drop-only=true ! video/x-raw,framerate=10/1
! filesink location=test_raw.I420
I've seen other examples online where people seem to be able to use video/x-raw(memory:NVMM) with videorate but with the above its not working for me.
I'm looking to decode and demux an mp4 file with gst-launch-1.0. Instead of using a bin - decodebin - I'd rather work with the seperate elements. Unfortunately, I did not find this.
My question is simple: what basic elements are contained in the decodebin?
If you can direct me to a place where I can find the composition of other bins or autopluggers that whould also be nice.
The decodebin will use all available elements in your gstreamer installation. Remember that you can launch the pipeline with decodebin and using verbose -v and guess what elements is the decodebin creating. For example, in the next pipeline that plays succesfully a mp4 file (video and audio):
gst-launch-1.0 -v filesrc location=/home/usuario/GST_/BigBuckBunny_320x180.mp4 ! queue ! qtdemux name=demuxer demuxer.video_0 ! queue ! decodebin ! videoconvert ! autovideosink demuxer.audio_0 ! queue ! decodebin ! audioconvert ! autoaudiosink
Watching the output I can conclude that the resulting pipeline is:
gst-launch-1.0 -v filesrc location=/home/usuario/GST_/BigBuckBunny_320x180.mp4 ! queue ! qtdemux name=demuxer demuxer.video_0 ! queue ! h264parse ! avdec_h264 ! videoconvert ! autovideosink demuxer.audio_0 ! queue ! aacparse ! avdec_aac ! audioconvert ! autoaudiosink
The playback components from gstreamer are available here. The playbin element will give you the full pipeline (video, audio, etc...) from the uri input.
For example, if you even don't know what kind of source you have, you can use playbin element:
gst-launch-1.0 playbin uri=file:///home/usuario/GST_/BigBuckBunny_320x180.mp4 -v
This will play automatically the file (if it is possible), and verbose output will show you the used plugins and status information.
gst-launch-1.0 can create .dot file with pipeline diagram every time pipeline changes state. To enable this functionality, set GST_DEBUG_DUMP_DOT_DIR variable to path where generated files should be saved. In this dir gst-launch-1.0 will create files like 0.00.00.069441527-gst-launch.READY_PAUSED.dot. You can then convert them to .png files using dot from ghraphviz package. To convert one file, use following command:
dot -Tpng 0.00.00.069441527-gst-launch.READY_PAUSED.dot -o0.00.00.069441527-gst-launch.READY_PAUSED.png
You also can convert them all, using following command in bash shell:
ls -1 *.dot | xargs -I{} dot -Tpng {} -o{}.png
You can find more details here:
How to generate a Gstreamer pipeline diagram (graph)
i am trying to share an h264 encoded data from gstreamer to another two processes(both are based on gstreamer).After some research only way i found is to use the shm plugin.
this is what i am trying to do
gstreamer--->h264 encoder--->shmsink
shmrc--->process1
shmrc--->process2
i was able to get raw data from videotestsrc and webcam working. But for h264 encoded data it doesn't.
this is my test pipeline
gst-launch-1.0 videotestsrc ! video/x-raw,width=640,height=480,format=YUY2 !
x264enc ! shmsink socket-path=/tmp/foo sync=true wait-for-
connection=false shm-size=10000000
gst-launch-1.0 shmsrc socket-path=/tmp/foo ! avdec_h264 ! video/x-
raw,width=640,height=480,framerate=25/1,format=YUY2 ! autovideosink
have anyone tried shm plugins with h264 encoded data, please help
Iam not aware of the capabilities of your sink used in "autovideosink", but as per my knowledge you either need to use videoconvert if the format supported by the sink (like kmssink or ximagesink) are different than provided by the source (in your case YUY2) or use videoparse if the camera format is supported by the sink. You may check this using gst-inspect-1.0 for the formats supported.
Anyways I am able to run your pipeline with some modifications using videoconvert in my setup :
./gst-launch-1.0 videotestsrc ! x264enc ! shmsink socket-path=/tmp/foo sync=true wait-for-connection=false shm-size=10000000
./gst-launch-1.0 shmsrc socket-path=/tmp/foo ! h264parse ! avdec_h264 ! videoconvert ! ximagesink
You may modify it as per the resolutions you want.
Kindly let me know if you face any issue with above.
I have two AXIS IP cameras streaming H264 stream over RTSP/RTP. Both cameras are set to synchronize with same NTP server so I assume both cameras will have same exact clock (may be minor diff in ms).
In my application, both cameras are pointing to same view and its required to process both camera images of same time. Thus, I want to synchronize the image capture using GStreamer.
I have tried invoking two pipelines separately on different cmd prompts but the videos are 2-3 seconds apart .
gst-launch rtspsrc location=rtsp://192.168.16.136:554/live ! rtph264depay ! h264parse ! splitmuxsink max-size-time=100000000 location=cam1_video_%d.mp4
gst-launch rtspsrc location=rtsp://192.168.16.186:554/live ! rtph264depay ! h264parse ! splitmuxsink max-size-time=100000000 location=cam2_video_%d.mp4
Can someone suggest a gstreamer pipeline to synchronize both H264 streams and record them into separate video files?
Thanks!
ARM
I am able to launch a pipeline using gst-launch as shown below. It shows good improvement on captured frame synchronization compare to lanuching two pipelines. Most times they differ by 0-500 msec. Though, I still want to synchronize them less than 150 msec accuracy.
rtspsrc location=rtsp://192.168.16.136:554/axis-media/media.amp?videocodec=h264 \
! rtph264depay ! h264parse \
! splitmuxsink max-size-time=10000000000 location=axis/video_136_%d.mp4 \
rtspsrc location=rtsp://192.168.16.186:554/axis-media/media.amp?videocodec=h264 \
! rtph264depay ! h264parse \
! splitmuxsink max-size-time=10000000000 location=axis/video_186_%d.mp4
Appreciate if someone can point other ideas!
~Arm
What do you mean synchronize? if you record to separate video files you do not need any synchronization.. as this is going to totaly separate them.. each RT(S)P stream will contain different timestamps, if you want to align them somehow to the same time (I mean real human time.. like "both should start from 15:00") then you have to configure them this way somehow (this is just idea)..
Also you did not tell us whats inside those rtp/rtsp streams (is it MPEG ts or pure IP.. etc). So I will give example of mpeg ts encapsulated rtp streams.
We will go step by step:
Suppose this is one camera just to demonstrate how it may look like:
gst-launch-1.0 -v videotestsrc ! videoconvert ! x264enc ! mpegtsmux ! rtpmp2tpay ! udpsink host=127.0.0.1 port=8888
Then this would be reciever (it must use rtmp2tdepay. We are encapsulating metadata inside MPEG container):
gst-launch-1.0 udpsrc port=8888 caps=application/x-rtp\,\ media\=\(string\)video\,\ encoding-name\=\(string\)MP2T ! rtpmp2tdepay ! decodebin ! videoconvert ! autovideosink
If you test this with your camera .. the autovideosink means that new window will popup displaying your camera..
Then you can try to store it inside file.. we will use mp4mux..
So for same camera input we do:
gst-launch-1.0 -e udpsrc port=8888 caps=application/x-rtp\,\ media\=\(string\)video\,\ encoding-name\=\(string\)MP2T ! rtpmp2tdepay ! tsdemux ! h264parse ! mp4mux ! filesink location=test.mp4
Explanation: We do not decode and reencode(waste of processing power) so I will just demux the MPEG ts stream and then instead of decoding H264 I will just parse it for the mp4mux which accepts video/x-h264.
Now you could use the same pipeline for each camera.. or you can just copypaste all elements into the same pipeline..
Now as you did not provide any - at least partial - attempt to make something out this is going to be your homework :) or make yourself more clear about the synchronization as I do not understand it..
UPDATE
After your update to question this answer is not very useful, but I will keep it here as reference. I have no idea how to synchronize that..
Another advise.. try to look at timestamps after udpsrc.. maybe they are synchronized already.. in that case you can use streamsynchronizer to synchronize two streams.. or maybe video/audio mixer:
gst-launch-1.0 udpsrc -v port=8888 ! identity silent=false ! fakesink
This should print the timestamps (PTS, DTS, Duration ..):
/GstPipeline:pipeline0/GstIdentity:identity0: last-message = chain ******* (identity0:sink) (1328 bytes, dts: 0:00:02.707033598, pts:0:00:02.707033598, duration: none, offset: -1, offset_end: -1, flags: 00004000 tag-memory ) 0x7f57dc016400
Compare PTS of each stream.. maybe you could combine two udpsrc in one pipeline and after each udpsrc put identity (with different name=something1) to make them start reception together..
HTH
I need to capture a video using a webcam and output a single image for each video frame captured.
I have tried using gstreamer with a multifilesink, e.g.:
gst-launch v4l2src device=/dev/video1 ! video/x-raw-yuv,framerate=30/1 ! ffmpegcolorspace ! pngenc ! multifilesink location="frame%d.png"
However, this does not actually output every frame, meaning that if I record for 2 seconds at 30 fps, I don't get 60 images. I'm assuming this is because the encoding can't go that fast, so I need another method.
I figured it might work if I have one pipeline capture a video, and a separate pipeline convert that video to frames, but I don't know enough about codecs. Do I need to encode the video to a file like h264 or mp4 just to then decode it again?
Does anyone have any thoughts or suggestions? Keep in mind that I need to be able to do this in code, not using an application like Adobe Premiere, for example.
Thanks!
You could simply add a queue in there like this:
gst-launch v4l2src device=/dev/video1 ! video/x-raw-yuv,framerate=30/1 ! queue ! ffmpegcolorspace ! pngenc ! multifilesink location="frame%d.png"
This should make sure the video-capture is allowed to run at 30 fps, and then writing it to
disk can happen in its own tempo. Just be aware that the queue will grow to quite a large size
if you leave this setup for too long.
the solution I have to offer doesn't use gstreamer but ffmpeg. I hope that's fine for you too.
As described in this forum post, you can use something like this:
ffmpeg -i movie.avi frame%d.png
to get a png/jpg image for each frame of the video.
But depending on the input file you use, you might have to convert it to an MPEG vid before running ffmpeg.
Note:
If you want leading zeroes in your image file names, use %05d instead (for 5-digit numbers, like in C's printf()):
ffmpeg -i movie.avi frame%05d.png
The output file format depends on the file extension, so you might use .jpg, .bmp, ... instead of .png.
I ended up doing this in two parts.
Write video to file.
gst-launch v4l2src device=/dev/video2 ! video/x-raw-yuv,framerate=30/1 ! xvidenc ! queue ! avimux ! filesink location=test.avi
Post process.
gst-launch-1.0 --gst-debug-level=3 filesrc location=test.avi ! decodebin ! queue ! autovideoconvert ! pngenc ! multifilesink location="frame%d.png"