I'm reading a byte-stream YUV420 at 972x720 pixels from a file with Gstreamer using the following command:
gst-launch-1.0 filesrc location=testfile blocksize=1049760 ! rawvideoparse width=972 height=720 framerate=1/1 ! xvimagesink
This works in so far that I get an image but it isn't displayed correctly. When exporting the frames seperately using command:
gst-launch-1.0 filesrc location=testfile blocksize=1049760 ! rawvideoparse width=972 height=720 framerate=1/1 ! multifilesink location="rvp_%d.raw"
I see that when using the element 'rawvideoparse' it will create a file of 1051200 bytes per frame instead of the expected 1049760. When I remove 'rawvideoparse' the frames are exported correctly but my objective is to read them directly from the file into an 'xvimagesink'
Where am I messing up?
Thanks to the GStreamer Development mailing list I got an answer. The problems was that the rawvideoparse element can't handle this resolution. When I switched to 976 width it works.
Related
I'm trying to save a MJPEG stream from a logitech C920 webcam to multiple video files (matroska).
I've got this pipeline: (1 mkv file every 60s)
gst-launch-1.0 -ev v4l2src device=/dev/video0 \
! image/jpeg,width=1280,height=720,framerate=24/1 \
! matroskamux ! multifilesink next-file=max-duration max-file-duration=60000000000 location='test1-%02d.mkv'
It outputs several files, as expected, but the files have errors, so tools like avidemux can't play them back. mkvalidator reports these:
WRN080: Unknown element [FF] at 293 size 88
WRN080: Unknown element [FF] at 494 size 64
WRN080: Unknown element [7D][01] at 566 size w98603107602
WRN801: The segment has no SeekHead section
WRN0B8: Track #1 is defined but has no frame
BTW, saving to a single file using filesink produces an mkv file without errors.
Is there a way to save multiple mkv files properly?
Any other container is also OK, but I cannot transcode (need low CPU load) and I cannot use raw (need HD with high fps).
I'm using GStreamer 1.8.2 on Ubuntu 16.04.1.
Thanks.
Update:
Following the advice below, I tried with splitmuxsink:
gst-launch-1.0 -e v4l2src device=/dev/video1 \
! image/jpeg,width=1280,height=720,framerate=24/1 \
! splitmuxsink muxer=matroskamux location='test1-%02d.mkv' \
max-size-time=10000000000
But it doesn't work: The file is never split and keeps growing in size.
The following pipeline seems to work:
gst-launch-1.0 -e v4l2src ! x264enc key-int-max=10 ! h264parse ! splitmuxsink muxer=matroskamux location='test1-%02d.mkv' max-size-time=60000000000
multifilesink doesn't know nothing about the container format, so you must use splitmuxsink to do the spliting.
Here is the quote from multifilesink doc:
It is not possible to use this element to create independently
playable mp4 files, use the splitmuxsink element for that instead.
I've got success with an upgraded GStreamer (Ubuntu 18.04)
$ gst-launch-1.0 --gst-version
GStreamer Core Library version 1.14.1
Here is a pipeline with an AVI container, where a new file is generated every ten seconds:
gst-launch-1.0 -e v4l2src device=/dev/video1 \
! image/jpeg,width=1280,height=720,framerate=24/1 \
! splitmuxsink muxer=avimux location='test1-%02d.avi' max-size-time=10000000000
It also works with matroskamux.
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
I'm have pipeline:
gst-launch-1.0 rtspsrc location=rtsp://ip/cam ! rtph264depay ! h264parse ! mp4mux fragment-duration=10000 streamable=1 ! multifilesink next-file=2 location=file-%03d.mp4
The first segment is played well, others not. When I'm try to view the structure of damaged mp4 see an interesting bug:
MOOV
Some data
MOOF
MDAT
MOOF
MDAT
The most interesting thing in "Some data". There is no header data, they simply exist. By block size I think it MDAT. I find size of the block and add before it MDAT header. File immediately becomes valid and playing. But the unknown piece can't be played because before it no MOOF header.
Problem is at mp4mux and qtmux. Tested on GStreamer 1.1.0 and 1.2.2. All results are identical.
Can use multifilesink not correct?
If you take look at documentation for multifilesink you will find the answer:
It is not possible to use this element to create independently playable mp4 files, use the splitmuxsink element for that instead. ...
So use splitmuxsink and don't forget to send EOS when you done to correct finish last file
Update
Looks like at time when question has been asked there wasn't such element like splitmuxsink
Can this be reproduced using videotestsrc instead of rtsp?
Try replacing your h264 receiving and depayloading with "videotestsrc num-buffers= ! x264enc ! mp4mux ..."
This might be a bug, please file it at https://bugzilla.gnome.org/enter_bug.cgi?product=GStreamer so it gets proper attention from maintainers.
Also, how are you trying to play it?
Thanks
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"
I am trying to run certain pipelines on the Command prompt for playing a video and I am often getting these errors/messages/warnings :
WARNING: erroneous pipeline: no element "qtdemux"
WARNING: erroneous pipeline: no element "playbin2"
WARNING: erroneous pipeline: no element "decodebin2"
ERROR: pipeline could not be constructed: no element "playbin".
Following are the pipelines :
gst-launch filesrc location=path to the mp4 file ! playbin2 ! queue ! ffmpegcolorspace ! autovideosink
or
gst-launch -v filesrc location=path to the mp4 file ! qtdemux name=demuxer ! { queue ! decodebin ! sdlvideosink } { demuxer. ! queue ! decodebin ! alsasink }
or
gst-launch -v playbin uri=path to the mp4 file
or
gst-launch -v playbin2 uri=path to the mp4 file
Questions
I wanted to know, if I am I missing the plugins to execute this.
How do I know which plugin is responsible for which or found where?
What is the benefit of implementing the pipeline via c code.Are the missing plugins still required.
Is it good to install the missing plugins form the Synaptic manager or form the Gstreamer site(base,good,bad,ugly)
When we do gst-inspect we get output like this:
postproc: postproc_hdeblock: LibPostProc hdeblock filter
libvisual: libvisual_oinksie: libvisual oinksie plugin plugin v.0.1
flump3dec: flump3dec: Fluendo MP3 Decoder (liboil build)
vorbis: vorbistag: VorbisTag
vorbis: vorbisparse: VorbisParse
vorbis: vorbisdec: Vorbis audio decoder
vorbis: vorbisenc: Vorbis audio encoder
coreindexers: fileindex: A index that stores entries in file
coreindexers: memindex: A index that stores entries in memory
amrnb: amrnbenc: AMR-NB audio encoder
amrnb: amrnbdec: AMR-NB audio decoder
audioresample: audioresample: Audio resampler
flv: flvmux: FLV muxer
flv: flvdemux: FLV Demuxer
What does the x : y ( x and y mean ) ?
Answers,
It looks like gstreamer at your ends was not installed correctly. playbin2, decodebin2 are basic and part of the base plugins
1 Yes you may be missing some plugins
2 Use gst-inspect command to check if it is available
3 From C code you can manage states, register callback, learn more
Yes missing plugins are still required
4 I guess gstreamer site would be better
5 Not sure about this one, would help if you arrange the result in a proper way
Most probably the GST_PLUGIN_PATH is incorrect. Please set the correct path to where the gstremer has been installed.