Video Compression

HDV uses MPEG-2 compression with a constant bit rate (CBR). I-, P-, and B-frames are used, creating a long-GOP pattern.

MPEG-2 video and audio are composed of a hierarchy of data streams:

åElementary stream: This can be a video, audio, subtitle, or other basic media stream. Formats like HDV contain both video and audio elementary streams.

åTransport stream: A transport stream encapsulates elementary streams for real-time distribution, such as television or Internet broadcast.

åProgram stream: A program stream also encapsulates elementary streams for content stored on media such as DVDs or hard disks.

HDV devices store and transmit elementary video and audio streams in an MPEG-2 transport stream. When you capture HDV video, Final Cut Pro automatically extracts the elementary video and audio streams from the transport stream and stores the data in tracks in a QuickTime media file.

Audio

HDV uses two audio tracks with a sample rate of 48 kHz and 16-bit resolution per sample. The audio is encoded using the MPEG-1 Layer 2 format with a data rate of 384 kbps.

Timecode

The timecode format of an HDV camcorder matches the frame rate of the video format. For example, 1080i50 footage uses 25 fps timecode.

Important: Some HDV camcorders do not record timecode, so you won’t be able to precisely recapture any clips if you delete the corresponding media files.

Chapter 1 Working with HDV

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Apple 6 manual Video Compression, Audio, Timecode
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6 specifications

The Apple iPhone 6, released in September 2014, marked a significant evolution in Apple's smartphone lineup. This model introduced a larger screen and a sleeker design, setting the stage for future devices in the iPhone series.

One of the most notable features of the iPhone 6 was its display. With a 4.7-inch Retina HD screen, the iPhone 6 offered a resolution of 1334 x 750 pixels, delivering vibrant colors and sharp images. This screen size was a departure from previous models, appealing to users who favored larger displays for better viewing experiences, whether for gaming, watching videos, or browsing the web.

The design of the iPhone 6 was another highlight. It featured a slim, curved aluminum body that not only made it more aesthetically pleasing but also improved its ergonomics. Weighing just 129 grams, the phone was light yet robust. The placement of volume buttons, the power button, and the headphone jack was thoughtfully designed to enhance usability.

Under the hood, the iPhone 6 was powered by the A8 chip, a 64-bit dual-core processor that offered impressive performance and energy efficiency. Coupled with the M8 motion coprocessor, the device could effectively handle demanding apps and services while optimizing battery life, providing users with a smooth experience throughout the day.

The camera capabilities of the iPhone 6 were also advanced for its time. It featured an 8-megapixel rear camera with optical image stabilization and a f/2.2 aperture, allowing for clearer low-light photography. The front-facing camera was improved as well, offering a 1.2-megapixel resolution and support for 720p HD video, making it great for selfies and video calls.

Connectivity options included LTE support, enabling faster download speeds, and Wi-Fi calling, which allowed users to make calls over Wi-Fi networks, enhancing communication in areas with poor cellular coverage. The iPhone 6 also introduced the Apple Pay feature, allowing users to make secure transactions using their devices.

In terms of software, the iPhone 6 originally came with iOS 8, which boasted new features such as HealthKit and HomeKit, further integrating technology into daily life. Regular software updates ensured that users could enjoy the latest features and security enhancements well into the device's lifecycle.

Overall, the iPhone 6 distinguished itself with a combination of innovative design, powerful performance, and a user-friendly experience, solidifying Apple's position in the smartphone market and paving the way for future iterations in the iPhone lineup.
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