Hi,
I would like to know if it is possible to transfer images over radio? It may include still images as bare minimum and videos if possible, i have an option to buy the e32 LoRa module, which according to my research has a bandwidth of 433MHz, distance is not a problem, but longer the better.
"Radio" is included in the electromagnetic spectrum, and is very often used to transmit images.
Inexpensive modules using the license free, low power bands like 433 MHz are fine for transmitting small, still images over short distances.
For video, drone FPV transmitter and receiver kits are quite cheap, e.g. HobbyWireless
Check you local laws on frequency spectrum. Those radios come in several different frequencies and not all of them are legal everywhere. For example the 433MHz units aren't legal in the US and the 915 MHz modules aren't legal in Europe.
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Of course it is! That is exactly what Television does, and it's how your phone gets image over WiFi or Cellular - both of which are "radio" technologies.
No: it uses a carrier frequency of 433MHz - the bandwidth is waaaaaaaaaay lower!
LoRa is designed for very low data rates - it would take many hours or even days to send a single still image.
LoRa is designed specifically for cases where distance is a big problem: the clue is in the name: "LoRa" = Long Range.
What range do you want?
Having said that, if you really do want to send images over LoRa - take a look at this:
It takes 40 minutes to send a single 320x240 image - but does send it over 3.5km.
The other key feature of LoRa is its low power - but I don't see that mentioned.
The FPV drone community has a lot of video transmitters that send NTSC (i think) video in real time. Most of these seem to work at 2.4GHz or 5.8GHz, which means that the range will be a bit less but may still be plenty for what you need.
I have a fast scan setup that sends NTSC at the very top of the 23cm band near 1.3GHz. With that system I have been able to send live video feeds over 4-5 km. But it requires an amateur radio license to operate.
Still images are not and issue for LoRa and there is a LoRa library that provides the routines and examples, either from SD card to SD card, or with Arducam or ESP32CAMs.
There is several articles on the topic here;
https://stuartsprojects.github.io/
In particular;
https://stuartsprojects.github.io/2021/09/20/Large-Data-Transfers-with-LoRa-Part3.html
433Mhz is not a good band for sending images, duty cycle limits would likely mean that if it takes 30 seconds to send an image, then you can only send one image every 300 seconds.
Then of course there is 2.4Ghz LoRa which is a good deal faster, few duty cycle limits but without the long range.
As for how fast you can send images, then at 433Mhz for a sample 63019 byte image I was getting a transfer time of 29.98 seconds, an achieved rate of 16,833bps. The on-air rate was 21,875bps.
How far that would go with good line of sight and legal antennas and powers, I dont know specifically, 25km to 50km probably.
Was that a compresed image, like jpeg?
Yes, this one in fact;
1024 x 744 pixels according to IrfanView, but you could send smaller or bigger ones.
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