33 lines
878 B
JavaScript
33 lines
878 B
JavaScript
module.exports = captureVideoFrame
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const {IllegalArgumentError} = require('./errors')
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function captureVideoFrame (video, format) {
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if (typeof video === 'string') {
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video = document.querySelector(video)
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}
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if (video == null || video.nodeName !== 'VIDEO') {
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throw new IllegalArgumentError('First argument must be a <video> element or selector')
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}
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if (format == null) {
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format = 'png'
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}
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if (format !== 'png' && format !== 'jpg' && format !== 'webp') {
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throw new IllegalArgumentError('Second argument must be one of "png", "jpg", or "webp"')
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}
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const canvas = document.createElement('canvas')
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canvas.width = video.videoWidth
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canvas.height = video.videoHeight
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canvas.getContext('2d').drawImage(video, 0, 0)
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const dataUri = canvas.toDataURL('image/' + format)
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const data = dataUri.split(',')[1]
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return new Buffer(data, 'base64')
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}
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