Pertemuan 2 : Citra Digital, Sampling, dan Quantization - Part 2 : Sejarah citra digital dan PCD

Made Windu Antara Kesiman

22 Aug 202105:28

Summary

TLDRThe video discusses the history of digital image processing, tracing its origins to the early 1920s when images were transmitted via undersea cables between London and New York for newspaper use. The first digital image, transmitted in 1921, was encoded using telegraph codes and printed with specialized equipment. As technology advanced, image quality improved from 5 to 15 levels of gray by 1929. However, true digital image processing, as defined today, only began with the advent of digital computers. The development of digital imaging was closely tied to the growth of computing and storage capabilities.

Takeaways

📜 The early use of digital images started in the newspaper industry.
🌍 The first digital image was transmitted between London and New York via an underwater cable in the early 1920s.
📰 This system allowed for faster transmission of news images across the Atlantic, reducing delivery time from one week to less than three hours.
🖨️ Special printing equipment was used to decode the transmitted image signals and reconstruct them for newspaper printing.
🖼️ The first digital image transmission occurred in 1921, using telegraph codes to send and print images.
⚙️ Initially, images were encoded in only 5 levels of gray, but by 1929, this was enhanced to 15 levels of gray.
👨‍🎨 An example from 1929 is the image of General Pershing, transmitted from London to New York and printed with 15 gray tones.
💻 Early digital images were not purely digital by today’s standards, as they did not involve computers in the process.
🖥️ The development of true digital image processing began with the rise of digital computers.
🔄 The advancement of digital image processing has always depended on the growth of digital computing power and storage capabilities.

Q & A

When did the first digital image transmission take place?
-The first digital image transmission took place in the early 1920s, where an image was sent via undersea cable between London and New York.
Which industry was the first to use digital images?
-The newspaper industry was the first to use digital images, primarily for transmitting news images across long distances.
What system was used to transmit images in the 1920s?
-A system called 'Bradley' was used to transmit images via telegraph codes over cables, enabling faster image transmission for newspapers.
How did the image transmission process work in the early 1920s?
-Images were encoded into telegraph codes and transmitted through undersea cables. Specialized printing equipment on the receiving end decoded and printed the images in newspapers.
How long did it take to transmit images across the Atlantic in the 1920s?
-The transmission time for images across the Atlantic was reduced from one week to less than three hours, thanks to the Bradley system.
What was the limitation of the early image transmission technology?
-Initially, the Bradley system could only transmit images in 5 levels of gray (5 shades of gray), limiting the quality and detail of the images.
How was the image transmission technology improved in 1929?
-In 1929, the technology was upgraded to transmit images with 15 levels of gray, resulting in higher-quality images with more tonal variations.
Why are early digital images not considered 'true' digital images?
-Early digital images were not considered 'true' digital images because they were transmitted using telegraph codes, without the involvement of digital computers in their processing.
What was the key factor that contributed to the evolution of digital image processing?
-The development of digital computers was the key factor that led to the true evolution of digital image processing, as computers enabled the storage and manipulation of digital data.
What are the main technological components involved in modern digital image processing?
-The main components are image capture sensors, storage devices, display technologies, and transmission systems capable of handling large amounts of digital image data.

Outlines

00:00

📜 The Origins of Digital Image Processing

The discussion begins by exploring the origins of digital image processing. The concept of transmitting digital images started in the newspaper industry, where the first image transmission occurred via underwater cables between London and New York in the 1920s. This system significantly accelerated the delivery of news images across the Atlantic, reducing transmission time from a week to just a few hours. Special printing equipment was essential for decoding and reconstructing the transmitted images for newspaper printing.

05:02

🖼️ Early Digital Image Transmission and Technological Improvements

In the following years, technological advancements improved the image transmission system. Initially, images could only be encoded in five shades of gray, but by 1929, this capability increased to 15 shades. The paragraph highlights a notable example of an image transmission in 1929, where a photo of General Pershing was sent from London to New York and printed with 15 levels of gray. Despite these advancements, the images were not yet considered fully digital, as they did not involve computers.

💻 Defining Digital Image Processing in the Context of Computer Technology

The paragraph emphasizes that early image transmission systems were not truly digital because they did not involve computers. It explains that the true definition of digital image processing only emerged with the development of digital computers. As computers evolved, so did the capabilities for processing and storing digital images, laying the foundation for modern digital imaging. The text also notes the high computational and storage demands required for processing digital images.

🔗 The Relationship Between Digital Image Processing and Computer Technology

The final paragraph concludes that the history of digital image processing is closely tied to the development of digital computers. As computers advanced, so did the ability to store and process large amounts of digital image data. The paragraph also mentions key aspects of digital image processing technology, such as capturing images with sensors, storing them, displaying them, and transmitting them, all of which rely heavily on advancements in digital technology.

Mindmap

Keywords

💡Digital Image

A digital image refers to a visual representation that is encoded in binary format, suitable for being processed or transmitted by a computer. In the video, the concept of 'Citra digital' is first introduced as images transmitted via telegraph for use in newspapers, marking the beginning of digital imaging technologies. Initially, these images were not truly digital since they did not involve computers, but they laid the groundwork for future digital image processing.

💡Telegraph Transmission

Telegraph transmission refers to the process of sending coded messages or images over long distances through wires. In the video, the speaker describes how, in the 1920s, images were transmitted across the Atlantic Ocean via telegraph cables between London and New York for newspaper printing. This early form of transmitting visual data is highlighted as a precursor to modern digital image processing.

💡Grey Levels

Grey levels refer to different shades between black and white in an image. In the context of the video, the first digital images could only represent five levels of grey, but by 1929, the technology had advanced to the point where images could be transmitted and printed with 15 levels of grey. This development illustrates the gradual improvement in image detail and quality in early digital imaging technologies.

💡Bradley System

The Bradley system was an early system used for transmitting images through cables. According to the video, this system was used in the 1920s to send images for newspapers across oceans. It represents a pivotal step in the history of digital imaging, particularly before the involvement of computers in image processing.

💡Newspaper Printing

Newspaper printing in the early 20th century involved the use of specialized printing equipment that could decode transmitted images and reconstruct them for print. The video discusses how images were transmitted via telegraph cables and printed using these machines. This method highlights how digital imaging was initially driven by the needs of industries like journalism, which needed faster and more efficient ways to share images.

💡Telegraf Codes

Telegraf codes were used to encode and transmit images through telegraph cables in the early days of digital image transmission. The video explains that the first images sent across the Atlantic were encoded using telegraph codes, which allowed newspapers in distant locations to receive and print images faster than ever before. This was an early example of data encoding for image transmission.

💡1920s Image Transmission

The 1920s marked the beginning of image transmission technology, which laid the groundwork for digital imaging. The video discusses how images were sent across the Atlantic using telegraph cables during this period, enabling newspapers to publish images much faster than through traditional methods. This historical milestone is significant in understanding the development of digital image processing.

💡General Pershing Image

The General Pershing image is one of the first significant examples of a digitally transmitted image. In the video, this image, sent in 1929 from London to New York, is noted for being transmitted with 15 levels of grey, demonstrating a major technological advancement in image quality. It serves as a historical landmark in the progression of digital imaging.

💡Computer Involvement in Digital Imaging

The video emphasizes that true digital image processing involves the use of computers. While early examples of 'digital' images from the 1920s did not involve computers, later advancements in digital imaging required significant computational power for encoding, processing, and storing large amounts of image data. This marks a turning point in the history of digital image processing.

💡Digital Storage and Transmission

Digital storage and transmission refer to the ability to store, manage, and send digital data, including images, using modern technology. The video highlights how the development of computer technology enabled the more efficient processing and transmission of digital images. This has been essential to the growth of digital imaging, as larger image files require more storage space and bandwidth to be transmitted effectively.

Highlights

The early stages of digital image processing began with the newspaper industry, where images were transmitted between London and New York via undersea cables in the 1920s.

The first image transmitted across the Atlantic was in 1921, reducing the time required for newspapers to receive images from one week to less than three hours.

The system used to transmit images relied heavily on specialized printing equipment, which decoded transmitted signals and reconstructed them as printable images.

The first digital images were not fully digital, as they still required specialized equipment and telegraph codes to transmit and print the images.

By 1929, image transmission technology advanced to support 15 levels of grayscale, improving the quality of printed images.

A notable image transmitted in 1929 was that of General Pershing, printed in 15 levels of grayscale after being transmitted from London to New York.

Although early digital image processes did not involve computers, they laid the groundwork for future digital image processing systems.

True digital image processing, as defined today, began with the development and use of digital computers, which could store and process large amounts of image data.

The advent of digital computers played a crucial role in the evolution of digital image processing, as they provided the computational power necessary for handling image data.

Early image transmission required significant storage and processing power, which was a challenge until digital computers became more advanced.

The process of digital image development depends on several factors, including capturing technology (sensors), storage methods, display technology, and transmission equipment.

Digital image processing also advanced alongside other digital technologies, such as transmission tools and display systems, which allowed for larger, more detailed images to be shared.

By the mid-20th century, the need for digital storage and computing capabilities increased as more detailed images required more storage space.

The history of digital image processing is closely tied to the history of computer development, with each advancement in computing power contributing to new capabilities in image processing.

In conclusion, the development of digital image processing is heavily reliant on advancements in digital computing technology, with each new innovation enabling further progress in the field.