gst-plugins-sonyalpha

This project provides a GStreamer demuxer, sonyalphademux, which produces regular JPEG frames from the Sony Alpha Liveview (Smart Remote) API.

Sony publish a list of cameras that support Remote API. This code is only tested on the Sony a6000 (ILCE-6000).

Building / installing the plugin

./autogen.sh
make
cp src/.libs/libgstsonyalpha.so ~/.local/share/gstreamer-1.0/plugins/

Setting up a Wi-Fi connection

Note: This shows an example connection with a Sony a6000 (ILCE-6000). Other cameras may have different URLs and menus.

1. Enable remote control from the camera

Press MENU.
Navigate to Airplane Mode, and set it to Off (if not already)
Navigate to Application List, and press ENTER
Select Smart Remote Embedded, and press ENTER

(If this is not present, you may need to update the firmware or install the application first.)

After it has started, the camera should indicate the Wi-Fi SSID and password to connect to.

2. Connect to the network from the computer

Connect to the Wi-Fi network indicated on the camera's screen.
Once the computer is connected, Smart Remote on the camera should show "Connecting..." It will continue to wait while you setup the rest of the connection.

Bootstrap the remote control API

API service discovery

The proper way to discover the camera is to do a UPnP SSDP request.

The messaging required is documented in Sony's SDK. If you're writing a program to interface with this camera, your code should discover the camera in this way.

If you just want to experiment... UPnP is hard. On the camera's Wi-Fi network, the default gateway is probably the camera's IP...

$ ip route
default via 192.168.122.1 dev wlp5s0  proto static  metric 600

The API root is /sony/ and is hosted on port 8080; so for this example the complete API URL is http://192.168.122.1:8080/sony/.

Submitting requests to the JSON-RPC endpoint

The camera has a HTTP endpoint that accepts command as JSON-encoded HTTP POST data.

Complete documentation is available in Sony's SDK, but important methods for activating liveview are noted here:

Get supported methods (getAvailableApiList)

$ curl -d '{"method": "getAvailableApiList","params": [],"id": 1,"version": "1.0"}' http://192.168.122.1:8080/sony/camera; echo ''
{"id":1,"result":[["getVersions","getMethodTypes","getApplicationInfo","getAvailableApiList","getEvent","startRecMode","stopRecMode"]]}

Start recording mode (startRecMode)

Despite the command name, this only makes the camera operate in remote shooting mode, giving access to all functionality:

$ curl -d '{"method": "startRecMode","params": [],"id": 1,"version": "1.0"}' http://192.168.122.1:8080/sony/camera; echo ''
{"id":1,"result":[0]}

Once in recording mode, getAvailableApiList should show more methods:

$ curl -d '{"method": "getAvailableApiList","params": [],"id": 1,"version": "1.0"}' http://192.168.122.1:8080/sony/camera; echo ''
{"id":1,"result":[["getVersions","getMethodTypes","getApplicationInfo","getAvailableApiList","getEvent","actTakePicture","stopRecMode","startLiveview","stopLiveview","actZoom","setSelfTimer","getSelfTimer","getAvailableSelfTimer","getSupportedSelfTimer","getExposureCompensation","getAvailableExposureCompensation","getSupportedExposureCompensation","setShootMode","getShootMode","getAvailableShootMode","getSupportedShootMode","getSupportedFlashMode"]]}

Start liveview mode (startLiveview)

Note: the camera must already be in recording mode to use this command.

$ curl -d '{"method": "startLiveview","params": [],"id": 1,"version": "1.0"}' http://192.168.122.1:8080/sony/camera; echo ''
{"id":1,"result":["http://192.168.122.1:8080/liveview/liveviewstream"]}

This will then give you a HTTP path where you can stream live camera images. You can stop and start accessing the liveview stream whenever you like.

This image format is described in the Framing Format docs, and is what sonyalphademux decodes!

Viewing the live stream with GStreamer

Once the camera has startRecMode and startLiveview (see above), you can build a simple GStreamer pipeline to watch the incoming video feed:

$ gst-launch-1.0 souphttpsrc location=http://192.168.122.1:8080/liveview/liveviewstream \
	! sonyalphademux ! jpegparse ! jpegdec ! videoconvert ! autovideosink

Recording the livestream with curl, and playing back with GStreamer

You can also save some frames for later using curl, then play them back with a similar pipeline:

$ curl http://192.168.122.1:8080/liveview/liveviewstream > /tmp/cameraframes
(Wait for 10 seconds) ^C
$ gst-launch-1.0 filesrc location=/tmp/cameraframes \
	! sonyalphademux ! jpegparse ! jpegdec ! videoconvert ! autovideosink

There is no audio on the stream, and the additional metadata from the frame_info payload is not read in this version of the demuxer.

The video is of a variable framerate and the demuxer does not advertise a frame size. You will discover the framesize from the jpegparse element. The framerate is variable.

Note: Smart Remote Embedded only allows one connection to stream live data from the camera. If you create a second connection and open the liveviewstream, the first connection will be dropped.

Copyright / License / Acknowledgements

License: LGPL 2+

This code is based on the multipartdemux plugin in gst-plugins-good:

Camera Remote API by Sony.

micolous/gst-plugins-sonyalpha