ADLINK Technology EVA SDK, User Manual, Page: 40 / 117

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Image Processing Plugins
The "idct-method" property controls the jpeg encoding method.
1. islow (0) – Slow, but accurate integer algorithm
2. ifast (1) – Faster, but less accurate integer method
3. float (2) – Floating-point: accurate, but faster speed depends on better hardware
The "quality" property sets the encoding quality within a range of 0 to 100, with a default setting of 85.
4.1.3 pngdec
This element decodes png images.
For more details, refer to the official documentation at:
https://gstreamer.freedesktop.org/documentation/png/pngdec.html?gi-language=c
4.1.3.1 Examples Using gst-launch
This pipeline transcodes a png to jpeg and saves it as a jpeg file.
gst-launch-1.0 filesrc location="frameP1.png" ! pngdec ! videoconvert ! jpegenc !
filesink location="framePJ1.jpeg"
Similarly, png images can be transcoded to tiff, bmp, or raw image formats.
gst-launch-1.0 filesrc location="frameP1.png" ! pngdec ! videoconvert !
avenc_tiff ! filesink location="framePT1.tiff"
gst-launch-1.0 filesrc location="frameP1.png" ! pngdec ! videoconvert !
avenc_bmp ! filesink location="frameB1.bmp"
gst-launch-1.0 filesrc location="frameP1.png" ! pngdec ! videoconvert ! filesink
location="framePR1.raw"
4.1.4 pngenc
This element encodes png images.
For more details, refer to the official documentation at:
https://gstreamer.freedesktop.org/documentation/png/pngenc.html?gi-language=c
4.1.4.1 Example Using gst-launch
This pipeline encodes the video test pattern to png images and saves them.
gst-launch-1.0 videotestsrc ! queue ! pngenc ! multifilesink
location="frame%d.png"
The "compression-level" property sets the PNG compression level within a range of 0 to 9, with a default setting of
6. A higher number creates a smaller file size..