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目前顯示的是 12月 14, 2018的文章

Making video fragment usable again

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up vote 0 down vote favorite I'm compiling a dataset of images for a machine learning project, and the easiest way to collect thousands of relevant images is by extracting frames from video. However to save on time, and given slow bandwidth, it would be most efficient if I could download segments of a video, and process them that way. I can do this easily on the command line via curl "url" -o "path/to/outputfile.mp4" -r "startbyte-endbyte" And I can normally split a video file into individual jpeg images via ffmpeg -i "path/to/video_file.mp4" "path/to/output/image%06d.jpg" However, the problem I have run into is that ffmpeg does not like it when I give it a video fragment, and gives the following error Invalid data found when processing input Further, attempting to use the tool Untrunc gives the following error Failed to parse atoms in truncated file I'm looking for any way to be able to process these file fragments....

Centrum Wiskunde & Informatica

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Centrum Wiskunde & Informatica Type National research institute Established 1946 President J. C. M. Baeten Administrative staff ~200 Location Amsterdam , Netherlands Website www.cwi.nl The Centrum Wiskunde & Informatica (abbr. CWI ; English: "National Research Institute for Mathematics and Computer Science") is a research center in the field of mathematics and theoretical computer science. It is part of the Netherlands Organisation for Scientific Research (NWO) and is located at the Amsterdam Science Park. This institute is famous as the creation ground of the Python Programming Language. It was a founding member of the European Research Consortium for Informatics and Mathematics (ERCIM). Contents 1 Early history 2 Recent research 3 European Internet 4 Spin-off companies 5 Software and languages 6 Notable people 7 References 8 External links Early history The institute was founded in 1946 by Johannes van der Corput, David van Dantzig, Jurjen Koksma, Hendrik A...

ESP8266/NodeMCU POST request returns -1 status code

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up vote -1 down vote favorite The following code gets a server response of -1. What am I doing wrong? I've done a bunch of research and this is the suggested code. I've tested the server code with Postman, and it works fine, so it must be the other code. Library used is ESP8266HTTPClient.h ESP8266 code void loop() HTTPClient http; http.begin("http://localhost:3003/record"); http.addHeader("Content-Type", "application/x-www-form-urlencoded"); int httpCode = http.POST("Message"); String payload = http.getString(); Serial.println(httpCode); // -1 Serial.println(payload); // nothing http.end(); Node Express server var express = require("express"); var router = express.Router(); router.post("/record", function(req, res) let message = req.body; console.log(message); res.status(200).send( message: message ); ); module.exports = router; Also tried a different API, with a GET request. Still doesn'...