Welcome to our OSD demo for the Analog Devices ADV 7625 26 27 HDMI transceiver chip. The OSD included is a low cost OSD solution with 16x16 single color boxes which we use here with high resolution and no scaling.
We run through our demo main menu here, all icons are 1 color icons except for the highlighted one which has 3 color smoothing applied to make it look more attractive. The selection box gradient is achieved using multiple Fbox, which supports up to 16 colors with border moving in harmony together. We show you also how it can look like in inverse video for the selection box. Then we move into the settings which shows similar icons and into our speaker setting which shows a sample single color image of a living room. Since all Tbox are single color, a compromise has to be made with number of colors and smoothing since each added color needs overlapping Tbox which then reduces to maximum image size that can be displayed.
Our screen saver kicks in here showing an animation driven by the MCU though SPI at about 10FPS in this case in order not to exceed SPI bus bandwidth and with an 8 color box spinning and moving along the screen even changing color as it hits the borders. Higher frame rates could be achieved with compromises and we leave to our customer to make this decision according to their desired specs.
The character based OSD is a simple 16x16 pixels single color array meant for text characters scalable from 1 to 15 times and we showed you in this demo how the character RAM can be used to create high resolution images.
For those familiar with the technical details of the OSD, it uses Tbox and Fbox to achieve this for its ability to cover more area on the screen with no scaling at all with Tbox able to display up to 16 different colors and Fbox up to 16 colors combining filled box color and border. More technical details on area coverage is included in the links below.
See the link below with this video for getting source code and Blimp download for ADV7625. Our document on Blimp OSD designer and Engineer Zone articles available from links below also have useful resource on limitation and where compromises that can be made early in product design phase for decision between image size vs number of colors and tricks on how to optimize your display.
Hope you have enjoyed our demo. Thanks for watching!
This ADV7625 OSD demo displays higher resolution image onto 720p resolution using Tbox image available in Blimp OSD Designer tool for NatureVue
ADV800x and Advantiv
ADV7625 .
An embedded video is also available at products:audio-video:analoghdmidvi-interfaces:adv7625:osd:tboximage-demo [Analog Devices Wiki]
