Multimedia Production Lecture 4 Digital Video Dr. Somsak Phattarasukol Faculty of Management Science UDON THANI RAJABHAT UNIVERSITY Digital Video ● Digital video is a representation of moving visual images in the form of encoded digital data. – the images being displayed are called frames – the rate at which frames are displayed in is called frame rate – the number of bits used to indicate a pixel's color is called color depth Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Digital Video ● An example video has – a duration of 1 hour (3600 sec), – a frame size of 640 x 480 pixels, – a color depth of 24 bits and – a frame rate of 25 frames per second would have a file size of 3600 x 640 x 480 x 24 x 25 = 82.8 Gbytes Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Digital Video Files ● Digital video file is a file for storing digital video and other data on a computer system. – It normally consists of a container containing encoded video data alongside encoded audio data as well as other data such as synchronization information and subtitles. – A program (or hardware) that encodes and decodes video or audio is called a codec Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Container ● A container is a metafile describing how different elements of data and metadata coexist in a computer file. – an example of image containers: TIFF – an example of audio containers: WAV – examples of multimedia containers: AVI, MP4, Ogg Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Codec ● A codec is a device or computer program capable of encoding or decoding a digital data stream or signal. – an audio codec is a program that compresses or decompresses digital audio data according to a given audio coding format – a video codec is a program that compresses or decompresses digital video, thus converting raw (uncompressed) digital video to a compressed format or vice-versa. Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Audio Coding Format ● An audio coding format (or audio compression format) is a content representation format for storage or transmission of digital audio. – Examples include MP3, AAC, Vorbis, and Opus. Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Video Coding Format ● A video coding format (or video compression format) is a content representation format for storage or transmission of digital video. – Examples include H.264 (MPEG-4 Part 10), Theora, Dirac, VP8, and VP9. Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Video File Format ● WebM – file extension: “.webm” – container: Matroska – audio coding format: Vorbis, Opus – video coding format: VP8, VP9 Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Video File Format ● Ogg – file extension: “.ogv, .ogg” – container: Ogg – audio coding format: Vorbis, FLAC – video coding format: Theora, Dirac Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Video File Format ● MP4 (MPEG-4 Part 14) – file extension: “.mp4, .m4p (with DRM), .m4v” – container: MPEG-4 Part 12 – audio coding format: AAC, MP3, others – video coding format: H.264 (MPEG-4 Part 10), MPEG-4 Part 2, MPEG-2, MPEG-1 Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Video File Format ● Flash Video (F4V) – file extension: “.flv” – container: MPEG-4 Part 12 – audio coding format: AAC, MP3 – video coding format: H.264 (MPEG-4 Part 10) Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Video File Format ● AVI – file extension: “.avi” – container: AVI – audio coding format: any – video coding format: any Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com MPEG ● The Moving Picture Experts Group (MPEG) is a working group of authorities that was formed by ISO and IEC to set standards for audio and video compression and transmission – MPEG-1 (1993): used on Video CD – MPEG-2 (1995): used on DVD Video – MPEG-4 (1998) – H.264 (MPEG-4 Part 10): used on Blu-ray Discs Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Video Production Process ● The video production process refers to the works required to complete a video product. – Pre-production phase – Production phase – Post-production phase Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Pre-production ● Pre-production refers to the tasks undertaken before the production phase begins, which includes. – Location scouting – Wardrobe preparation – Production schedule – Set construction – Script read-through with cast and director Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Production ● Production refers to the process in which video footage is recorded. – The production phase is also known as principal photography. – This is when actors on sets, cameras rolling, etc. Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Post-production ● Post-production refers to the works after shooting is done (after the production phase ends), which includes: – Editing video footage – Adding sound effects, music, etc. – Adding special effects – Adding titles and graphics – Re-shooting certain scenes if required Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Video Editing ● Video editing is the process of manipulating and rearranging video shots to create a new work. – Remove unwanted footage – Choose the best footage – Create a flow – Give the video a particular "angle" Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Types of Video Editing ● There are several different ways to edit video and each method has its pros and cons. – Film splicing – Linear editing – Non-linear editing – Live editing Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Linear Editing ● In linear editing, video footage is selectively copied from one tape (source) to another (blank master) in the desired length and order – Pro: simple and trouble-free method – Con: must be done in a linear fashion – starting with the first shot and working through to the last shot Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Non-linear Editing ● In non-linear editing, video footage is stored in a computer and then edited using specialized software. – Pro: very flexible – it allows you to make changes to any part of the video at any time – Cons: requires expensive hardware and software and difficult to learn Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Video Editing Software ● Video editing software is a computer program which handles the post-production video editing of digital video sequences – It is typically based on a timeline interface where sections of video, known as clips, are laid out in sequence and played back. Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Video Editing Software ● There is a wide range of video editing software available – Advanced software (such as Adobe Premiere) offers a range of tools for editing (e.g. color manipulation, sound mixing and visual effects) but is expensive and requires a high-end computer to run effectively. – Free (or cheap) software (such as Windows Movie Maker) is limited in functions and may not be practical for real-world usage. Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Video Editing Software ● Most video editing software does at least three things: – Capture: recording the footage – Edit: trimming, cutting and arranging clips across the timeline – Output: exporting the finished video product in the chosen formats and resolution. Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Capturing ● Video footage needs to be captured and transferred from a source machine (e.g. video camera) to a computer's hard drive. – AVCHD is a file format for the digital recording and playback of high-definition video in high-end camcorders developed jointly by Sony and Panasonic. – AVCHD uses the H.264 (MPEG-4 Part 10) for video compression and supports both Dolby AC-3 (Dolby Digital) for audio compression. Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Editing ● Video editing software typically has three main work areas: – Project Window: contains all of the elements (video clips, audio, graphics, etc) used in the current project – Monitor Window: shows the videoes you are working on (one monitor for the source and one for the master edit) – Timeline Window: represents the flow of the video project and is the place where you insert video and other elements and arrange them as desired. Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Editing ● Below is a screen-shot from Adobe Premiere CS6 Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Outputting ● What needs to be considered when outputting your video: – What video formats does your software support? – Will it be watched over the Internet using a fast connection? – Will it be watched using a DVD or Blu-ray player? – What are the longevity of the video format you chose? Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com Outputting ● For example, – Flash is a very popular video format and its distributor (Adobe) will still be around for a while. – Flash doesn't play on Apple's product. – H.264 (MPEG-4 Part 10) is a forward-looking, high- quality, versatile video format and supported by Microsoft, Apple and Adobe. Sources: Wikipedia.org, dpbestflow.org, Mediacollege.com and Videomaker.com.