Pictures on Audio Tape - No Joke!

Some old 8-bit home computers were able to load and save data onto cassettes, and some of that data was pictures. I thought if they could be recorded onto tape digitally, surely they can be recorded onto tape in analogue. Well, I found a program that can do that, it encodes the picture to an analogue audio signal, and then it can be recorded onto any sound recorder. If the sound is analysed on a spectrogram, you will see the orginal picture.

I looked into this a bit, and from what I could find out, this method was actually used to transmit pictures though radio back in the 60's, some rock bands even put them into their songs and the odd one or two have appeared here and here. I think it's called slow scan TV spectrograph or forier or something like that. I do already know you can could record 32-line Baird TV transmissions onto audio tape as they fit within the audio bandwidth, they used phonograph records to record them when it was used in the 30's, but recording and sending still pictures encoded to audio has a lot more detail.

Category:

Science & Technology

Tags:

• picture
• to
• audio
• tape
• encode
• decode
• slow
• scan
• tv
• spectrogaph
• spectrogram
• forier
• audiopaint
• sonic
• visualiser
• cool
• dude
• clem

[LiviuJETIX]

what is that thing on 1:07 i can't recognize that that thing it looks like cartoon monitor with face

[CoolDudeClem]

@LiviuJETIX It's a telebug, a cartoon that aired in the early 80 about robots with TVs for heads, you're probably not old enough to remember that series.

[noisedownloader]

In an inverse way, one day I used VHS to record Audio and it worked, seem to me that Tape is Tape and records anything that can be recorded. Nothing more

[CoolDudeClem]

@noisedownloader If that VHS had HI-FI stereo, that would have been a very good recording, some early HI-FI VHS recorders actually had an audio-only mode for doing that.

[jamesjan]

feeling sick after watching your "blairwitch"-like camera handling.

cool stuff but the shaking almost made my throw up.

[CoolDudeClem]

@jamesjan Not all my videos are like that, it was just easier without the tripod.

[fueledbymusic3]

Same idea as those floppy disks. And computer cassettes.

[MustNotRead]

that picture sounds cool and the sound looks cool too. wow, i think my head's going to explode

[raymond9987654321]

cool

[MadManMarkAu]

This is not SSTV. This is directly synthesizing a frequency spectrum using images as the volume for each spectrum chunk. This is a rudimentary wideband method. Very cool, though.

SSTV uses frequency-shift keying (a single tone shifted around higher and lower) to represent the video signal in much the same format as composite video on your VCR, only much slower. Each scanline is synced with a low sync pulse. Each frame has a "header" and "footer" area. Modern modes even support color images. :)

[NBF27]

Try searching for SSTV, Amateur Radio has been doing stuff like this for years. We send Images, Text and Morse all using sound, this could be easier to record to Tape. Try MMSSTV or HRD (HAM Radio Deluxe) if you want to try decoding most of the stuff. I'm sure you can record this to Tape in the same way although you will need a Radio Licence to transmit.

[andiegurgel]

Try NBTV!

[ElectroMecca]

So like in the beginning I'm laughing "She's just a modem", but this signal never stops being analog really, right? just like old school TV wasn't digital?

[Vintagesoundz14]

whats the program you used to encode the picture to analog audio signal and what softare did you use to get it back from audio to picture, i want to try this at home.

[Vintagesoundz14]

could it ry this with an ordinary cassette recorder, please could you do a quick video or inbox message about how you did this i would like to try this.

[ObiTrev]

@CoolDudeClem I remember ReBoot though! Also, ever tried recording data onto a VHS tape?

[Filmer1eX]

To easily decode these kind of messages google for "Coagula Light". Though when it comes to transmitting images over audio I prefer plain old SSTV (best software for it as far as I know is MMSSTV). Supports not only colored images, but using some high quality settings you can actually transmit them in very good quality too (though the clip will be very long, almost 5 minutes if you use the highest settings)