53 lines
1.5 KiB
TypeScript
53 lines
1.5 KiB
TypeScript
import extract from 'png-chunks-extract';
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import encode from 'png-chunks-encode';
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import textKey from 'png-chunk-text'
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export const PngMetadata = {
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write: (pngBuffer: Uint8Array, metadata: Record<string, string>): Buffer => {
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let chunks:{
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name:string
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data:Uint8Array
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}[] = extract(Buffer.from(pngBuffer));
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chunks = chunks.filter((v) => {
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return v.name.toLocaleLowerCase() !== 'text'
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})
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for (const key in metadata) {
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const value = metadata[key];
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chunks.splice(-1, 0, textKey.encode(key, value))
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}
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const encoded = encode(chunks);
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return encoded
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},
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writeStream:(pngBuffer: Uint8Array, metadata: Record<string, string>): Buffer => {
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let chunks:{
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name:string
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data:Uint8Array
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}[] = extract(Buffer.from(pngBuffer));
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chunks = chunks.filter((v) => {
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return v.name.toLocaleLowerCase() !== 'text'
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})
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for (const key in metadata) {
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const value = metadata[key];
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chunks.splice(-1, 0, textKey.encode(key, value))
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}
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const encoded = encode(chunks);
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return encoded
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},
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filter: (pngBuffer: Uint8Array) => {
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let chunks:{
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name:string
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data:Uint8Array
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}[] = extract(Buffer.from(pngBuffer));
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chunks = chunks.filter((v) => {
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return v.name.toLocaleLowerCase() !== 'text'
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})
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const encoded = encode(chunks);
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return encoded
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}
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} |