1. Image File Format Only focused in TIFF-Tag Image File Format Grayscale 8 bit Purpose-interchange of digital image data Goals: Extensibility-capable to adapt new type of image Portable-different environment Revisable-edit, change & process (not read only)

2. Tag refers to file’s basic structure Tag provides information : Width Length Number of pixel Store in Tag Directory Tag Directory have not set length/ number just a pointer-so can grow and adapt in future

3. Image consist 2D array of number The array store color intensity of each pixel location TIFF format Header Image File Directories Data

4. Arrangement of Header, IFD and Data in TIFF file Header Image File Directories Data

5. File Header: First 8 byte of file Same format in all TIFF file and constant Contains first IFD offset Image File Directories-IFD Provides image information such as image width, length, bits per pixel, etc

6. Data Contains real data for specific information such as pixel value and etc Can show after or before IFD

7. File Header Format Byte Order-How data will be read from file : LSB-Intel($4949) MSB-Motorola($4D4D) Version-TIFF version number IFD Offset-First IFD offset or address MSB-must do swap 2 or 4 byte 8 byte Byte Order Version Offset of the First IFD

8. IFD Format Number of DE => m DE-0 DE-1 …………….. DE-(m-1) Offset of the Next IFD m*12 tag type length value 12 Directory Entry Image File Directories

9. In IFD contains DE In first 2 byte IFD, provides number of DE, m DE has 12 byte each So in each IFD, total number of DE is m x 12

10. DE format: Tag Type of information the entries contains First 2 bytes Data Type 2 bytes Data type of information and data size

11. TIFF data type 1 = byte – 8 bit unsigned integer 2 = ASCII – 8 bit bytes that store ASCII codes (last byte must be null) 3 = short – 16 bit (2 byte) unsigned integer 4 = long – 32 bit (4 byte) unsigned integer 5 = rational – 2 long:first is numerator. Second denominator

12. Length Length of the information 4 bytes Depend to Tag variable real size S = Length x Size that define from Type

13. Value 4 bytes Data contents If S > 4 bytes value contains is not real information just an offset or address or pointer for real information Else value contains real information