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T351 - Summer Week 5 Agenda / Reality check
Lecture & lab today:
Readings:
Final Projects: review criteria All of your written materials (excluding footage logs) should be typed. They should be submitted in a final project production packet. The amount of detail along with the appearance and packaging of your materials & packet affects your grade.
Advanced Editing (cont.) Timeline Techniques
Exporting footage If you want to use After Effects or some other software to add animation to a clip, you'll need to be able to access the clip from the aniation software. If you're working on the same computer, you don't have to export a clip. Instead use the browser (F9 key) and find what it's called and where it's located. Then you can gop to After Effects and simply import it from where it's located. After Effects won't change your original clip- but will create a new movie which you can import into your project. Exporting by Reference If you want to bring an entire sequence fo series of clips into After Effects, use "export by reference". Again you can only do this if exporting to another application with access to the same media. Using "export by reference", you create a file that points or references the existing media and doesn't recreate it. File Management and Archiving We can't keep all of our data forever. There are several scenarios you need to know how to deal with:
Become familiar with the Media Manager. Use it to back up and archive your project. Engineering, Maintenance & Troubleshooting Termination: Even if you have a $1,000 monitor connected to your $15,000 camera, your video can look terrible if it is not properly terminated. Analog (composite) video signals need to be terminated or fed into something with 75 ohms of resistance. If not the picture will suffer. “T” barrels or “Y” connectors for video and “loop through” inputs on video recorders and monitors are useful but can easily lead to trouble unless the signal is properly terminated. If a device has only one input then you can assume it will be properly terminated internally into 75 ohms. If a device has a loop through input and a termination switch, you must switch it to “75 ohms on” if there is nothing else connected. If there is another device connected, or daisy-chained, then you must switch the termination switch to off or open. At the end of the chain, the termination will be set to 75 ohms. If you don't have a termination switch use a small BNC terminator- they should be one in every gear bag. What is the lifespan of video gear? Everything you have in your kit will break and is eventually destined for the junkyard. It’s a fact. – It’s a matter of when. When do you think it’ll break? When it’s sitting on the shelf? Probably out on a shoot. When you’re shooting b-roll or interviewing the Mayor? Jim’s Double Backup / Plan B (for important shoots it’s nice to have two of everything) I bring extra microphones, bulbs & cameras etc. Troubleshooting Every field producer must know how to troubleshoot Audio is the most common problem but video can be vexing. Major Troubleshooting Principle: Swap connectors & the problem moves. This would mean the problem is toward the source. If you swap cables and the problem doesn’t move- it means the trouble is towards the destination. This technique can help you pinpoint problems. Virtual Problem Scenarios – These are actual problems you may encounter. How many steps will it take you to find: Bad Audio
PS: Audio hum- don’t run power cords near or parallel to audio cables. If you must, cross wires at 90 degrees. Bad Video
-------------------------------- Off-line & On-line Traditionally one of the purposes of off-line systems were to create EDLs that could be brought into higher-end on-line systems. The first non-linear editors (D Vision and early Avids) were sophisticated off-line systems that could not only generate an EDL, but let the editors work with VHS like quality. With advances in technology non-linear editing system got steadily better, and today off-the-shelf PC or Macs are capable of editing on-line video. EDL (edit decision list) Edited programs often need to be rebuilt or re-edited from the raw ingredients or source files they were created from. When a program is edited, you can create and save an EDL corresponding to the master tape or master sequence in the timeline. An EDL is a simple ASCI text file that describes the events. Once created, an EDL can be used to re-edit the project. A good EDL allows sequences to be recreated with frame accuracy, including placement and types of transitions. Most editing systems- both linear and non-linear, create an EDL as you assemble or create the project. Each edit made adds a decision in the list. EDL example:
What’s in an EDL? (Structure) The EDL usually starts with a title, date and the time code information (drop-frame, non drop frame). Comments are preceded by the REM flag. Each edit becomes an event in the list. A single event describes the reel names or source, (BL means black), track type (V, A1, A2), and transition (cut, wipe, dissolve or key) along with the source tape time code in and out points, followed by the record tape time code in and out points. Note that events with dissolves take two lines to describe the event. They might start with a cut, then the dissolve that takes place. Remember that semicolons (;) denote drop-frame and regular colons (:) signify non-drop frame. The EDL created by an editing system is typically unique to that system, but follows one of a handful of standard formats:
List Management Software Imagine you have a good EDL, but one of your source reels gets dubbed to another tape. During the dub process, the time code wasn't regenerated, but started anew. Assigning a new start time for a reel is just one thing list management software lets you do. You can also adjust your list in a variety of ways. You can also map your EDL from drop to non-drop, add & remove edits, & even remap wipe codes for different switchers. Week 5 Lab: Timeline Techniques
Exporting footage If you want to use After Effects or some other software to add animation to a clip, you'll need to be able to access the clip from the aniation software. If you're working on the same computer, you don't have to export a clip. Instead use the browser (F9 key) and find what it's called and where it's located. Then you can gop to After Effects and simply import it from where it's located. After Effects won't change your original clip- but will create a new movie which you can import into your project. Exporting by Reference If you want to bring an entire sequence fo series of clips into After Effects, use "export by reference". Again you can only do this if exporting to another application with access to the same media. Using "export by reference", you create a file that points or references the existing media and doesn't recreate it. File Management and Archiving We can't keep all of our data forever. There are several scenarios you need to know how to deal with:
------------------------------------------------------------------------ Thursday Lab: Agenda:
Video for Multimedia Video from a non-linear editor often needs to be converted for uses other than television. Other uses include:
Each of these applications use different codecs and technologies. It's important to understand the difference between multimedia systems (the container or supporting architecture) and codecs, which are specific file types. Popular mutlimedia systems include Windows Media and Quicktime. Both of these systems support a range of different codecs. In many cases you can export your video directly from your editing software into the appropriate codec. Sometimes you need specialized or proprietary hardware or software. Video DVDs use the MPEG-2 codec. There are both hardware and software converters. Many hardware converters can process in real-time. Software converters take longer but can provide high-quality results.
The Internet supports many competing architectures: Windows, Quicktime & Real. Websites often offer video at vaying bandwidths, but often use just one of the three architectures. You've discoveed this if you've ever found that you couldn't play video from a website untll installing the right plug-in for your browser Examples:
Software like Cleaner or Flip4Mac can take a movie and output it in a variety of formats and resolutions You could use it to make three different versions of a movie, each with three different connection speeds. Format Conversion Editors will have to deal with a number of different media formats and need to understand the physical distinction between them. Some of the different formats include film, standard definition and high definition versions of NTSC, PAL, 16 x 9 and 4 x 3. NTSC (National Television Systems Committee) definition of standard definition TV, (used in North America, some of South America, Japan, etc) uses a frame rate close to 30, roughly 29.97 frames per second. There are 525 scan lines; approximately 480 of these are visible. The HD (high definition) standard for broadcast has been created by the ATSC, the Advanced Television Systems Committee, which was formed at the urging of the FCC to establish standards for the new high definition formats. PAL (Phase Alternate Line) is used in most of Europe, Australia, & Asia and runs at 25 frames per second using 625 lines. SECAM (Sequential Color and Memory) If possible it’s best to edit in the media’s native format. If you have high-quality PAL footage, it’s best to try to keep it in PAL. If you have 24 fps footage, it’s best to keep it in 24 fps. That way you won’t get conversion artifacts from changing frame rates and generation losses. But while ideal, we can’t always practice this. Often we’ll get a tape from another country, or that contains another type of media that must be integrated into our existing content. How can you get from one format to another? You can use hardware or software. Hardware: Companies like Snell & Willcox make conversion boxes. Panasonic makes a multi-format conversion VCR (PAL, SECAM & NTSC) Film to Video (or 24P to 30i) When converting film to video we use a 3:2 Pulldown See Film runs at 24 frames per second. 24p refers to video shot at 24 frames per second progressive- that means there are no fields. Since film runs at 24 fps and video runs about 30 fps, the two aren't directly interchangeable at least on a frame for frame basis. (To be more precise, 23.976 film frames become 29.97 video frames.) In order to transfer film to 30 fps video, the film frames must be precisely sequenced into a combination of video frames and fields. A telecine is a piece of hardware containing a film projector sequenced with a video capture system. The telecine process is a term used to describe the process of converting film to video, also called a 3 2 pulldown. In the 3-2 pulldown each frame of film gets converted to 2 or 3 fields of video. Note how 4 (24fps) frames are converted to 5 interlaced frames (30 fps).
The problem with converting film frames to fields, is that some video frames have fields from two different film frames. If you think about it you'll see that this can present all types of problems. DTV (Digital TV broadcasting) TV Broadcasters are supposed to broadcast totally in digital by 2007, so the analog spectrum can be reclaimed for other purposes. DTV doesn't necessarily mean high-definition. DTV broadcasts can be either HD (High Definition) or SD (standard definition). You can squeeze 4 SD programs in the same space used to broadcast one HD program. Both use MPEG-2 compression. SD vs. HD SD works in both 4:3 and 16:9. Its video pixel dimensions include: HD is 16:9. Its video pixel dimensions include: Video frame rates: 24p, 30p, 30i, 60p, or 60i. HD has 4 discreet channels of audio. Beside having more pixel resolution, HD can display much more information in terms of color and brightness. HD has a much larger contrast ration than SD. It's not film, but it's getting close. Cybercollege reading: http://www.cybercollege.com/dtv_stans.htm Shooting and editing HDTV See:
Shooting HDTV For starters, remember that there are two basic means of compressing video:
Cameras range from consumer models that can be found for about $1,000 to high-end cameras costing over $200,000. Generally speaking, camcorders with high quality lenses that are capable of writing higher data rates and recording images up to 1920 x 1080 pixels in varying frame rates will be at the higher end of the price range. Camcorders with lower quality optics that use lower data rates, GOP-based compression, and have fewer frame rate options will occupy the lower end of the price range. Editing in HD You can edit HD with most recent versions of Final Cut Pro. The trick is getting the video into the computer and monitoring it. To do this you need the right hardware. A few systems out there now include:
HDTV data may be brought into a computer through FireWire, HD-SDI, or digital or analog component capture. Footage can be transferred into an editing system bit for bit, or can be encoded into a codec more suitable for editing. While GOP-based video (such as HDV) is inexpensive and can be brought into editing systems via firewire connections, it is extremely taxing for the CPU to edit. Just adding dissolves and simple titles can require many minutes of rendering time. In order to output a sequence from FCP via firewire back onto an HDV deck requires "conforming." This is assembling the video data into a data stream with a GOP-based structure (MPEG-2). Intraframe HD video (such as DVCPRO HD) are easier for the computer to process, but require faster data read/write speeds. They can be output directly from the system onto tape via digital conenctions (firewire or HD-SDI). Generally speaking, higher end editing systems that routinely work with intraframe HD video require RAIDs in order to achieve fast enough read and write speeds. Vocabulary (Know these terms)
Final Test Review Final Exam is worth 70 points! The best way to review for it is to study the class notes and the midterm (expect everything you got wrong on the midterm to be on the final). The final will be true/false, multple choice, and short answer. It will cover the following areas:
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