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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 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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