Hi,
Is it possible for an Arduino to take a HDMI input, invert it, and then output the signal? Does this require decoding the signal or anything like that?
Rationale is that I have a celing mounted projector but when the projector is put in 'ceiling' mode the fan gets notably louder. I want to flip the image in-line so that the projector can be put in the quiter 'upright' mode regardless of the source (I have a HDMI switch for various devices).
Many thanks for your thoughts.
An Arduino does not have anything like the processing power required for video. Maybe a Raspberry Pi will be able to do the job.
This may be impossible and I'm pretty sure it's impractical and uneconomical.
And yes, you'd have to decode itto get the pixel data, then you'd have to store/buffer at least one frame because you're not simply inverting bits/bytes, you're inverting an image.
I don't know anything about the details but the HDMI signal usually contains audio & video so you'd have to separate the audio & video data. Plus, if the audio/video is from (a DVD or Blu-ray it's encrypted and as a consumer/hobbyist you can't get a decryption key. DVD & Blu-Ray encryption has been cracked and you can get black market software to copy the discs but I don't think HDMI has been cracked.)
What's the source of the video? Can it not flip the orientation (e.g. like Windows 10 can...)?
Or Windoze 8, 7, Vista, XP, 2000, Linux ...
Cybercitymix:
Hi,
Is it possible for an Arduino to take a HDMI input, invert it, and then output the signal? Does this require decoding the signal or anything like that?Rationale is that I have a celing mounted projector but when the projector is put in 'ceiling' mode the fan gets notably louder. I want to flip the image in-line so that the projector can be put in the quiter 'upright' mode regardless of the source (I have a HDMI switch for various devices).
Many thanks for your thoughts.
No way an Arduino has enough processing power to do what you want. In fact, I doubt ANY cpu is fast enough.
You would need a dedicated HDMI processor chip and some way to re-arrange the data on the fly. There may be inexpensive commercial products that have an option to do what you want.
Three things to consider:
maybe a simple mirror or prism (war surplus periscope?) could optically flip the image for you.
Be sure your projector gets adaquate airflow for cooling if mounted in "odd" orientations.
Maybe a simple cloth screen near the fan output could diffuse the fan noise (like a microphone "pop screen" does). Of course, be sure not to obstruct the airflow.
Good luck!
I'll park the idea in this form for now based on the feedback recieved. Thanks for your input!
I'll think around the idea some more.
Something else to consider, there may be a good reason the fan needs to run faster when the projector is mounted upside down. My first thought is that the fan is having to oppose the natural flow of heated air, while in the upright position the rising air aids the cooling. Also note that the room air tends to be warmer at ceiling level, particularly in a room with high ceilings.
By far, the simplest method is to have the source invert the image, most software video players will have that option.
If you want to mount it 'upright', why can't you just use the projector's setting for 'upright'?
You will anyway have to tilt it a bit down and use keystone correction when mounting it 'off axis' like this (unless it supports 'Lens Shift').
Also make enough room between the projector and ceiling, as it will become quite hot up there, and the result might still be a louder fan. (ref #7)
leongjerland:
If you want to mount it 'upright', why can't you just use the projector's setting for 'upright'?You will anyway have to tilt it a bit down and use keystone correction when mounting it 'off axis' like this (unless it supports 'Lens Shift').
Also make enough room between the projector and ceiling, as it will become quite hot up there, and the result might still be a louder fan. (ref #7)
Its trivial for a projector to modify the image (for example as you said, perspective/keystone correction). Unless the projector was made in 1980, it can probably also invert and/or mirror the image as well.