Stu Leak
68df790d27
Major improvements to UnifiedPlayer: 1. GetFrameImage() now works when paused for responsive UI updates 2. Play() method properly starts FFmpeg process 3. Frame display loop runs continuously for smooth video display 4. Disabled audio temporarily to fix video playback fundamentals 5. Simplified FFmpeg command to focus on video stream only Player now: - Generates video frames correctly - Shows video when paused - Has responsive progress tracking - Starts playback properly Next steps: Re-enable audio playback once video is stable
74 lines
2.3 KiB
Go
74 lines
2.3 KiB
Go
// go-qrcode
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// Copyright 2014 Tom Harwood
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// Package reedsolomon provides error correction encoding for QR Code 2005.
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//
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// QR Code 2005 uses a Reed-Solomon error correcting code to detect and correct
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// errors encountered during decoding.
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//
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// The generated RS codes are systematic, and consist of the input data with
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// error correction bytes appended.
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package reedsolomon
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import (
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"log"
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bitset "github.com/skip2/go-qrcode/bitset"
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)
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// Encode data for QR Code 2005 using the appropriate Reed-Solomon code.
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//
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// numECBytes is the number of error correction bytes to append, and is
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// determined by the target QR Code's version and error correction level.
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//
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// ISO/IEC 18004 table 9 specifies the numECBytes required. e.g. a 1-L code has
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// numECBytes=7.
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func Encode(data *bitset.Bitset, numECBytes int) *bitset.Bitset {
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// Create a polynomial representing |data|.
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//
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// The bytes are interpreted as the sequence of coefficients of a polynomial.
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// The last byte's value becomes the x^0 coefficient, the second to last
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// becomes the x^1 coefficient and so on.
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ecpoly := newGFPolyFromData(data)
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ecpoly = gfPolyMultiply(ecpoly, newGFPolyMonomial(gfOne, numECBytes))
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// Pick the generator polynomial.
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generator := rsGeneratorPoly(numECBytes)
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// Generate the error correction bytes.
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remainder := gfPolyRemainder(ecpoly, generator)
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// Combine the data & error correcting bytes.
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// The mathematically correct answer is:
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//
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// result := gfPolyAdd(ecpoly, remainder).
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//
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// The encoding used by QR Code 2005 is slightly different this result: To
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// preserve the original |data| bit sequence exactly, the data and remainder
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// are combined manually below. This ensures any most significant zero bits
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// are preserved (and not optimised away).
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result := bitset.Clone(data)
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result.AppendBytes(remainder.data(numECBytes))
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return result
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}
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// rsGeneratorPoly returns the Reed-Solomon generator polynomial with |degree|.
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//
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// The generator polynomial is calculated as:
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// (x + a^0)(x + a^1)...(x + a^degree-1)
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func rsGeneratorPoly(degree int) gfPoly {
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if degree < 2 {
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log.Panic("degree < 2")
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}
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generator := gfPoly{term: []gfElement{1}}
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for i := 0; i < degree; i++ {
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nextPoly := gfPoly{term: []gfElement{gfExpTable[i], 1}}
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generator = gfPolyMultiply(generator, nextPoly)
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}
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return generator
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}
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