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On 07/05/2016 16:31, hw wrote: |
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> Helmut Jarausch schrieb: |
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>> On 04/08/2016 03:26:53 PM, hw wrote: |
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>>> |
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>>> Hi, |
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>>> |
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>>> what would be the best approach to extract data |
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>>> from a screencast? |
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>>> |
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>>> The task is to acquire some data from the display of |
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>>> a GUI program used interactively by a user. There are |
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>>> a couple 'fields' (as in "designated areas of the display") |
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>>> in which the relevant data is being displayed while the |
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>>> program is being used. The acquired data needs to be |
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>>> entered into a mysql database, preferably as soon as |
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>>> possible. (The program needs windoze, and the sources |
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>>> are unavailable :( ) |
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>>> |
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>>> |
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>>> The idea is to make a screen recording and postprocess |
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>>> the recording with some sort of OCR software. This might |
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>>> require using ffmpeg (or the like) to create a single |
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>>> image from each frame of the recording; then treat each |
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>>> image with an OCR software to get the interesting data |
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>>> which can then be entered into the database. |
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>>> |
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>>> Data to extract is mostly numbers. The relevant fields |
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>>> can be expected to be either filled or empty. The FPS rate |
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>>> of the recording can be kept reasonably low, like 1 FPS, |
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>>> or perhaps even less, depending on how frequent the relevant |
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>>> fields change. |
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>>> |
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>>> Using tesseract comes to mind, but after reading that |
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>>> |
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>>> "Tesseract's output will be very poor quality if the input |
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>>> images are not preprocessed to suit it: Images (especially |
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>>> screenshots) must be scaled up such that the text x-height |
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>>> is at least 20 pixels,[12] any rotation or skew must be |
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>>> corrected or no text will be recognized, low-frequency |
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>>> changes in brightness must be high-pass filtered, or |
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>>> Tesseract's binarization stage will destroy much of the |
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>>> page, and dark borders must be manually removed, or they |
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>>> will be misinterpreted as characters."[1] |
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>>> |
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>>> I'm even more doubtful that this would produce usable |
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>>> results with sufficient reliability. |
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>>> |
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>>> So what might be the best way to get text/numbers out of |
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>>> what a program displays? |
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>>> |
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>>> |
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>>> [1]: https://en.wikipedia.org/wiki/Tesseract_(software) |
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>>> |
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>> |
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>> I can't help with Gentoo. |
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>> Try to find an old (free) version of FineReader which runs under wine. |
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>> If you do it only occasionally, transfer the image to an Android phone |
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>> where there a good and cheap OCR apps, even FineReader. |
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> |
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> It would be too much video to process. Besides, phones are |
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> ok for making phone calls and entirely incompatible with |
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> computers, which makes them useless for anything else but |
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> making phone calls. |
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Huh? da fuck you talkin' 'bout? |
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My trusty collection of Android devices would be very surprised to hear |
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they now don't have real CPUs, wifi chips, RAM and storage. Or can't run |
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a web browser, do email, instant chat, play x264 video with less cpu |
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load than my 8 core laptop, share with smb on the network, do bluetooth, |
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video calls or any of the other bazzillion things computers have always |
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done with each other. |
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How odd. I really thought my Android phones could do all of that. I must |
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have imagined it .... that means my delusions are worse than I thought |
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and maybe I need different and more pills from the nice lady who's my GP. |
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-- |
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Alan McKinnon |
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alan.mckinnon@×××××.com |
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