@eris/exif - npm Package Compare versions

Comparing version 0.4.1-alpha.3 to 0.4.1-alpha.4

dist/decoder/ifd-entry.d.ts

@@ -1,3 +0,5 @@
-import { IIFDEntry, IReader, IFDTagName } from '../utils/types';
+/// <reference types="node" />
+import { IIFDEntry, IReader, IFDTagName, Endian } from '../utils/types';
 export declare class IFDEntry implements IIFDEntry {
+    startOffset: number;
     tag: number;
@@ -7,3 +9,3 @@ dataType: number;
     private readonly dataReader;
-    constructor(tag: number, dataType: number, length: number, dataReader: IReader);
+    constructor(startOffset: number, tag: number, dataType: number, length: number, dataReader: IReader);
     readonly lengthInBytes: number;
@@ -14,2 +16,3 @@ readonly friendlyTagName: IFDTagName;
     static read(reader: IReader): IFDEntry;
+    static mutate(buffer: Buffer, simpleEntry: IIFDEntry, data: Buffer, endianness: Endian): Buffer;
 }

dist/decoder/ifd-entry.js

@@ -6,5 +6,8 @@ "use strict";
 const log_1 = require("../utils/log");
+const writer_1 = require("../utils/writer");
+const reader_1 = require("../utils/reader");
 const log = log_1.createLogger('ifd-entry');
 class IFDEntry {
-    constructor(tag, dataType, length, dataReader) {
+    constructor(startOffset, tag, dataType, length, dataReader) {
+        this.startOffset = startOffset;
         this.tag = tag;
@@ -70,2 +73,3 @@ this.dataType = dataType;
     static read(reader) {
+        const startOffset = reader.getPosition();
         const tag = reader.read(2);
@@ -76,6 +80,29 @@ const dataType = reader.read(2);
         log.verbose(`read tag ${tag}`, dataReader);
-        return new IFDEntry(tag, dataType, length, dataReader);
+        return new IFDEntry(startOffset, tag, dataType, length, dataReader);
     }
+    static mutate(buffer, simpleEntry, data, endianness) {
+        if (simpleEntry.dataType !== types_1.IFDDataType.String)
+            throw new Error('Can only mutate strings');
+        // Always ensure the string ends with null terminator
+        if (data[data.length - 1] !== 0)
+            data = Buffer.concat([data, Buffer.from([0])]);
+        // Read the real IFD so we have something better to work with
+        const reader = new reader_1.Reader(buffer, simpleEntry.startOffset);
+        reader.setEndianess(endianness);
+        const entry = IFDEntry.read(reader);
+        if (entry.lengthInBytes <= 4)
+            throw new Error('Can only change strings of length >3');
+        // Replace the length with the new length
+        const newLength = data.length;
+        const writer = new writer_1.Writer(buffer, { dangerouslyAvoidCopy: true });
+        writer.setEndianess(endianness);
+        writer.seek(entry.startOffset + 4);
+        writer.write(newLength, 4);
+        // Replace the data itself
+        entry.dataReader.seek(0);
+        const dataOffset = entry.dataReader.read(4);
+        return writer_1.Writer.spliceBufferRange(buffer, data, dataOffset, dataOffset + entry.lengthInBytes);
+    }
 }
 exports.IFDEntry = IFDEntry;
 //# sourceMappingURL=ifd-entry.js.map

dist/decoder/tiff-decoder.d.ts

@@ -1,3 +0,5 @@
-import { IGenericMetadata, IBufferLike, IJPEGOptions } from '../utils/types';
+/// <reference types="node" />
+import { IGenericMetadata, IBufferLike, IJPEGOptions, IIFDEntry, IFDTagName } from '../utils/types';
 export declare class TIFFDecoder {
+    private readonly _buffer;
     private readonly _reader;
@@ -15,2 +17,4 @@ private _ifds;
     extractMetadata(): IGenericMetadata;
+    extractIFDEntries(): IIFDEntry[];
+    static replaceIFDEntry(decoder: TIFFDecoder, tag: IFDTagName, data: Buffer): Buffer;
 }

dist/decoder/tiff-decoder.js

@@ -10,5 +10,7 @@ "use strict";
 const log_1 = require("../utils/log");
+const ifd_entry_1 = require("./ifd-entry");
 const log = log_1.createLogger('decoder');
 class TIFFDecoder {
     constructor(buffer) {
+        this._buffer = buffer;
         this._reader = new reader_1.Reader(buffer);
@@ -166,4 +168,15 @@ }
     }
+    extractIFDEntries() {
+        this._readAndValidateHeader();
+        this._readIFDs();
+        return this._ifds.map(ifd => ifd.entries).reduce((a, b) => a.concat(b), []);
+    }
+    static replaceIFDEntry(decoder, tag, data) {
+        const ifd = decoder.extractIFDEntries().find(ifd => tags_1.getFriendlyName(ifd.tag) === tag);
+        if (!ifd)
+            throw new Error(`Could not find "${tag}" in buffer`);
+        return ifd_entry_1.IFDEntry.mutate(Buffer.from(decoder._buffer), ifd, data, decoder._reader.getEndianess());
+    }
 }
 exports.TIFFDecoder = TIFFDecoder;
 //# sourceMappingURL=tiff-decoder.js.map

dist/encoder/xmp-encoder.js

@@ -6,2 +6,3 @@ "use strict";
 const keywords_parser_1 = require("../metadata/keywords-parser");
+const writableTags = Object.assign({}, tags_1.xmpTags, { DateTimeOriginal: true });
 const log = log_1.createLogger('xmp-encoder');
@@ -55,4 +56,4 @@ const XMP_BASE_FILE = `
             const tagName = key;
-            if (!(tagName in tags_1.xmpTags)) {
-                log(`skipping ${tagName} which is not an XMP tag`);
+            if (!(tagName in writableTags)) {
+                log(`skipping ${tagName} which is not a writable tag`);
                 continue;
@@ -140,2 +141,4 @@ }
     static _buildReplacement(tagName, value) {
+        if (tagName === 'DateTimeOriginal')
+            return `exif:DateTimeOriginal="${value}"`;
         if (tagName !== 'DCSubjectBagOfWords')
@@ -142,0 +145,0 @@ return `xmp:${tagName}="${value}"`;

dist/utils/reader.d.ts

@@ -9,2 +9,3 @@ import { IBufferLike, IReader, Endian } from '../utils/types';
     getPosition(): number;
+    getEndianess(): Endian;
     setEndianess(endian: Endian): void;
@@ -11,0 +12,0 @@ read(length: number): number;

dist/utils/reader.js

@@ -16,2 +16,5 @@ "use strict";
     }
+    getEndianess() {
+        return this._endianness;
+    }
     setEndianess(endian) {
@@ -18,0 +21,0 @@ this._endianness = endian;

dist/utils/types.d.ts

@@ -16,2 +16,3 @@ /// <reference types="node" />
     getPosition(): number;
+    getEndianess(): Endian;
     setEndianess(endian: Endian): void;
@@ -46,2 +47,3 @@ read(length: number): number;
 export interface IIFDEntry {
+    startOffset: number;
     tag: number;
@@ -95,2 +97,5 @@ dataType: number;
 }
+export interface IWriterOptions {
+    dangerouslyAvoidCopy?: boolean;
+}
 export interface IJPEGOptions {
@@ -97,0 +102,0 @@ skipMetadata?: boolean;

dist/utils/writer.d.ts

@@ -1,2 +0,3 @@
-import { IBufferLike, IWriter, Endian } from '../utils/types';
+/// <reference types="node" />
+import { IBufferLike, IWriter, Endian, IWriterOptions } from '../utils/types';
 export declare class Writer implements IWriter {
@@ -6,3 +7,3 @@ private readonly _bytes;
     private _endianness;
-    constructor(buffer?: IBufferLike);
+    constructor(buffer?: IBufferLike, options?: IWriterOptions);
     getPosition(): number;
@@ -17,2 +18,3 @@ setEndianess(endian: Endian): void;
     toBuffer(): IBufferLike;
+    static spliceBufferRange(buffer: Buffer, replacement: Buffer, start: number, end: number): Buffer;
 }

dist/utils/writer.js

@@ -5,8 +5,12 @@ "use strict";
 class Writer {
-    constructor(buffer) {
+    constructor(buffer, options = {}) {
         this._bytes = [];
         this._position = 0;
         this._endianness = types_1.Endian.Big;
-        if (buffer)
-            this.writeBuffer(buffer);
+        if (buffer) {
+            if (options.dangerouslyAvoidCopy)
+                this._bytes = buffer;
+            else
+                this.writeBuffer(buffer);
+        }
     }
@@ -67,4 +71,9 @@ getPosition() {
     }
+    static spliceBufferRange(buffer, replacement, start, end) {
+        const preamble = buffer.slice(0, start);
+        const postamble = buffer.slice(end);
+        return Buffer.concat([preamble, replacement, postamble]);
+    }
 }
 exports.Writer = Writer;
 //# sourceMappingURL=writer.js.map

lib/decoder/ifd-entry.ts

 import {getFriendlyName} from '../utils/tags'
-import {IFDDataType, IIFDEntry, IReader, IFDTagName, getDataTypeSize} from '../utils/types'
+import {IFDDataType, IIFDEntry, IReader, IFDTagName, getDataTypeSize, Endian} from '../utils/types'
 import {createLogger} from '../utils/log'
+import {Writer} from '../utils/writer'
+import {Reader} from '../utils/reader'
 
@@ -9,2 +11,3 @@ const log = createLogger('ifd-entry')
   public constructor(
+    public startOffset: number,
     public tag: number,
@@ -80,2 +83,3 @@ public dataType: number,
   public static read(reader: IReader): IFDEntry {
+    const startOffset = reader.getPosition()
     const tag = reader.read(2)
@@ -87,4 +91,32 @@ const dataType = reader.read(2)
     log.verbose(`read tag ${tag}`, dataReader)
-    return new IFDEntry(tag, dataType, length, dataReader)
+    return new IFDEntry(startOffset, tag, dataType, length, dataReader)
   }
+
+  public static mutate(
+    buffer: Buffer,
+    simpleEntry: IIFDEntry,
+    data: Buffer,
+    endianness: Endian,
+  ): Buffer {
+    if (simpleEntry.dataType !== IFDDataType.String) throw new Error('Can only mutate strings')
+    // Always ensure the string ends with null terminator
+    if (data[data.length - 1] !== 0) data = Buffer.concat([data, Buffer.from([0])])
+    // Read the real IFD so we have something better to work with
+    const reader = new Reader(buffer, simpleEntry.startOffset)
+    reader.setEndianess(endianness)
+    const entry = IFDEntry.read(reader)
+    if (entry.lengthInBytes <= 4) throw new Error('Can only change strings of length >3')
+
+    // Replace the length with the new length
+    const newLength = data.length
+    const writer = new Writer(buffer, {dangerouslyAvoidCopy: true})
+    writer.setEndianess(endianness)
+    writer.seek(entry.startOffset + 4)
+    writer.write(newLength, 4)
+
+    // Replace the data itself
+    entry.dataReader.seek(0)
+    const dataOffset = entry.dataReader.read(4)
+    return Writer.spliceBufferRange(buffer, data, dataOffset, dataOffset + entry.lengthInBytes)
+  }
 }

lib/decoder/tiff-decoder.ts

@@ -17,4 +17,7 @@ import {IFD} from '../decoder/ifd'
   IJPEGOptions,
+  IIFDEntry,
+  IFDTagName,
 } from '../utils/types'
 import {createLogger} from '../utils/log'
+import {IFDEntry} from './ifd-entry'
 
@@ -30,2 +33,3 @@ const log = createLogger('decoder')
 export class TIFFDecoder {
+  private readonly _buffer: IBufferLike
   private readonly _reader: IReader
@@ -37,2 +41,3 @@ private _ifds: IIFD[]
   public constructor(buffer: IBufferLike) {
+    this._buffer = buffer
     this._reader = new Reader(buffer)
@@ -209,2 +214,14 @@ }
   }
+
+  public extractIFDEntries(): IIFDEntry[] {
+    this._readAndValidateHeader()
+    this._readIFDs()
+    return this._ifds.map(ifd => ifd.entries).reduce((a, b) => a.concat(b), [])
+  }
+
+  public static replaceIFDEntry(decoder: TIFFDecoder, tag: IFDTagName, data: Buffer): Buffer {
+    const ifd = decoder.extractIFDEntries().find(ifd => getFriendlyName(ifd.tag) === tag)
+    if (!ifd) throw new Error(`Could not find "${tag}" in buffer`)
+    return IFDEntry.mutate(Buffer.from(decoder._buffer), ifd, data, decoder._reader.getEndianess())
+  }
 }

lib/encoder/xmp-encoder.ts

@@ -1,2 +0,2 @@
-import {IGenericMetadata, IBufferLike} from '../utils/types'
+import {IGenericMetadata, IBufferLike, XMPTagName} from '../utils/types'
 import {xmpTags} from '../utils/tags'
@@ -6,2 +6,7 @@ import {createLogger} from '../utils/log'
 
+const writableTags: Record<XMPTagName | 'DateTimeOriginal', boolean> = {
+  ...xmpTags,
+  DateTimeOriginal: true,
+}
+
 const log = createLogger('xmp-encoder')
@@ -66,4 +71,4 @@
 
-      if (!(tagName in xmpTags)) {
-        log(`skipping ${tagName} which is not an XMP tag`)
+      if (!(tagName in writableTags)) {
+        log(`skipping ${tagName} which is not a writable tag`)
         continue
@@ -174,2 +179,3 @@ }
   ): string {
+    if (tagName === 'DateTimeOriginal') return `exif:DateTimeOriginal="${value}"`
     if (tagName !== 'DCSubjectBagOfWords') return `xmp:${tagName}="${value}"`
@@ -176,0 +182,0 @@ const keywords = parseKeywords({DCSubjectBagOfWords: value})

lib/utils/reader.ts

@@ -18,2 +18,6 @@ import {IBufferLike, IReader, Endian} from '../utils/types'
 
+  public getEndianess(): Endian {
+    return this._endianness
+  }
+
   public setEndianess(endian: Endian): void {
@@ -20,0 +24,0 @@ this._endianness = endian

lib/utils/types.ts

@@ -19,2 +19,3 @@ export interface ILogger {
   getPosition(): number
+  getEndianess(): Endian
   setEndianess(endian: Endian): void
@@ -54,2 +55,3 @@ read(length: number): number
 export interface IIFDEntry {
+  startOffset: number
   tag: number
@@ -110,2 +112,6 @@ dataType: number
 
+export interface IWriterOptions {
+  dangerouslyAvoidCopy?: boolean
+}
+
 export interface IJPEGOptions {
@@ -112,0 +118,0 @@ skipMetadata?: boolean

lib/utils/writer.ts

@@ -1,9 +0,9 @@
-import {IBufferLike, IWriter, Endian} from '../utils/types'
+import {IBufferLike, IWriter, Endian, IWriterOptions} from '../utils/types'
 
 export class Writer implements IWriter {
-  private readonly _bytes: number[]
+  private readonly _bytes: number[] | IBufferLike
   private _position: number
   private _endianness: Endian
 
-  public constructor(buffer?: IBufferLike) {
+  public constructor(buffer?: IBufferLike, options: IWriterOptions = {}) {
     this._bytes = []
@@ -13,3 +13,6 @@ this._position = 0
 
-    if (buffer) this.writeBuffer(buffer)
+    if (buffer) {
+      if (options.dangerouslyAvoidCopy) this._bytes = buffer
+      else this.writeBuffer(buffer)
+    }
   }
@@ -79,2 +82,13 @@
   }
+
+  public static spliceBufferRange(
+    buffer: Buffer,
+    replacement: Buffer,
+    start: number,
+    end: number,
+  ): Buffer {
+    const preamble = buffer.slice(0, start)
+    const postamble = buffer.slice(end)
+    return Buffer.concat([preamble, replacement, postamble])
+  }
 }

package.json

 {
   "name": "@eris/exif",
-  "version": "0.4.1-alpha.3",
+  "version": "0.4.1-alpha.4",
   "description": "Parses EXIF data.",
@@ -40,3 +40,3 @@ "main": "./dist/index.js",
   },
-  "gitHead": "b8b08c09d1f2d26d4a5a9363866e43e340bf6c0f"
+  "gitHead": "411a3177ed2583d528bbf2ecc0b769f9253d34c1"
 }

No alert changes

Improved metrics

Total package byte prevSize

231278

increased by3.89%

Lines of code

4257

increased by3.4%

No dependency changes