Schematic import from a Jpeg  - Page 1
Forum section: electronics / general

author: Deathwish
author_rank: Unknown
timestamp: June 11, 2015, 10:13:46 pm
content: I dont have any software on my pc's for doing schematics, but is there something that can import a jpg file that is rather dire and then redraw it with minimal interaction.

author: Tandy
author_rank: Frequent Contributor
timestamp: June 11, 2015, 10:47:29 pm
content: Seems like a rather complex task that would require OCR to recognise text, a raster to vector conversion for lines and then some way of determining which lines are nets and which are component symbols and outlines. If such software exists the complexity would suggest it would not be free or cheap.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: June 12, 2015, 12:36:08 am
content: To what end? Just annotating or redrawing parts of it? Do it in MS Paint.And get that sucker out of JPG as soon and as often as possible. JPG is the worst format for line drawings (see).Related reading:http://seventransistorlabs.com/tmoranwms/Elec_Circuit_Rules.htmlTimP.S. Gah, I wanted to use a hyperlink. But the board automatically embeds YT links! You can't win.

author: Deathwish
author_rank: Unknown
timestamp: June 12, 2015, 01:36:52 am
content: I havea manual that is a naff pdf format, all the text is grey and becoming unreadable, the schematic is the same, I want to reclaim it to full glory with black text but keep the images the same as they are. So far I am using finereader and Omnipage. some of it is ok but not what i really want , for programme or so that is meant to be professional it is not doing a very good job of re writing text it recognises as proper text but merely a shade of grey and blurry

author: John_ITIC
author_rank: Frequent Contributor
timestamp: June 12, 2015, 02:20:00 am
content: Well, JPG is a bitmap format so cannot be read but merely interpreted/guessed at what information is there. I'd say forget about trying to read anything useful from an image. This would be massively complex so better to just use your brain to redraw whatever information is in JPG form today into schematics form.

author: SL4P
author_rank: Super Contributor
timestamp: June 12, 2015, 03:10:55 am
content: Scan it at the highest contrast / readability you can.Paste it into your preferred schematic editor,as a background element, and start redrawing using new schematic editor primitivesoverthe original.You can create your own library to reflect the original device symbols - and should end up with an almost perfect 'new' copy.Delete the background image, and just do a visual check for obvious mistakes (crossing lines etc)

author: amyk
author_rank: Super Contributor
timestamp: June 12, 2015, 12:44:06 pm
content: Quote from: Deathwish on June 12, 2015, 01:36:52 amHow long is the manual? Others here might be willing to help you digitise text if OCR isn't working so well. Depending on the subject matter I may be interested too.As others have mentioned, redrawing the schematics would be the best way to go there.

author: Deathwish
author_rank: Unknown
timestamp: June 12, 2015, 02:32:29 pm
content: Its only a frequency gen, and I sorted it out all but the schematics. I left that alone.

author: Zero999
author_rank: Super Contributor
timestamp: June 12, 2015, 04:57:45 pm
content: I use imaging software to increase the contrast as much as possible, convert it to monochrome so the lines are either black or white and save as PNG.Why not post it and I'll have a go at clearing it up?

author: Deathwish
author_rank: Unknown
timestamp: June 12, 2015, 05:24:03 pm
content: Quote from: Hero999 on June 12, 2015, 04:57:45 pmIt is copyrighted material and I believe Dave says not to post such on his forum . It is only a service manual for the Farnell FG3. Its old but still working ( intermittently ) and I intend to take it to bits, replace the caps and Transistors in it then hope it works properly again.

author: Deathwish
author_rank: Unknown
timestamp: June 12, 2015, 05:39:13 pm
content: original manualhttp://www.filedropper.com/farnellfg3functiongeneratorwhat I have managed so farhttp://www.filedropper.com/binder1My problem is more the schematics because I have trouble with my eyesight and its a pain trying to read values on it.

author: Zero999
author_rank: Super Contributor
timestamp: June 12, 2015, 07:31:26 pm
content: I had a go. This is the best I can do.

author: Deathwish
author_rank: Unknown
timestamp: June 12, 2015, 07:33:39 pm
content: thanks. I just wish that these programes would add a electronic dictionary of symbols etc.

author: timofonic
author_rank: Frequent Contributor
timestamp: June 12, 2015, 09:17:28 pm
content: Quote from: Deathwish on June 12, 2015, 07:33:39 pmOpamps, transistors, capacitors, transformer, voltage outputs...Unfortunately most values aren't visible

author: suicidaleggroll
author_rank: Super Contributor
timestamp: June 12, 2015, 09:25:01 pm
content: Quote from: Circuiteromalaguito on June 12, 2015, 09:17:28 pmThey all seem readable to me. I haven't found any yet that I couldn't decipher. With a little work that shouldn't be difficult to replicate in a schematic program, values and all. I found the original much easier to read than the BW one from Hero though. Nothing against his efforts, just sometimes you need the greyscale to pick up the light marks that complete the symbol, but aren't dark enough to pass the threshold for "black". The human eye/mind is still better at pattern recognition than any image processing algorithm, at least any you'll find in an off the shelf photo manipulation program.

author: ranch varment
author_rank: Regular Contributor
timestamp: June 12, 2015, 10:17:25 pm
content: Thats an ac beasty alright with all those grounds and dc converts everywhere.

author: Deathwish
author_rank: Unknown
timestamp: June 12, 2015, 10:32:53 pm
content: I like it, its old and whilst not exactly in the same category as the latest Ghz or Mhz stuff it is solid, it puts out a decent signal on spec. My counter picks it up on the 100Khz as 100Khz on all types of function. It fooled me to start with as on some of them you have to have 2 buttons pressed in and I never noticed it till I took a good look at the front .... always pays to look first

author: timofonic
author_rank: Frequent Contributor
timestamp: June 13, 2015, 12:57:41 am
content: I'll look at it better after I finish my exams at 19 June. If nobody does it before, I'll make a schematic in KiCad so I'll have an excuse to learn to use it

author: amyk
author_rank: Super Contributor
timestamp: June 13, 2015, 12:44:12 pm
content: I took few dozen minutes and traced out most of it - just need to finish adding the labels.

author: Deathwish
author_rank: Unknown
timestamp: June 13, 2015, 01:12:13 pm
content: Quote from: amyk on June 13, 2015, 12:44:12 pmawesome

author: timofonic
author_rank: Frequent Contributor
timestamp: June 13, 2015, 02:11:37 pm
content: Quote from: amyk on June 13, 2015, 12:44:12 pmWhat software do you use?

author: amyk
author_rank: Super Contributor
timestamp: June 14, 2015, 12:24:28 pm
content: Done. Please check that the values are correct, some of them like 15 and 18 are hard to tell apart.Quote from: Circuiteromalaguito on June 13, 2015, 02:11:37 pmAdobe Illustrator. It's no schematic editor but since I wanted to replicate the style I didn't want to change the settings of my real schematic editor, and I'm just as fast with it for drawing other things.

author: Deathwish
author_rank: Unknown
timestamp: June 14, 2015, 12:44:05 pm
content: More than a little impressed !. will hopefully open my beastie up later , take a snap of the inside then replace it in the manual add the schematic you have done and post it for all. At least there will be one around again that all can read and use.

author: Deathwish
author_rank: Unknown
timestamp: June 21, 2015, 12:04:49 am
content: Picture of the inside