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cartTutorials a Safe Harbor blogLive Capture using Matrox MXO2 Mini
Today’s handheld HD camcorders offer amazing quality for their cost and size, but there is a price to be paid for the portability - the video is captured using compression. Without compression, the video files would be so large that the camera’s recording capacity would be used up in a matter of minutes! There are several types of compression that can be applied to reduce the overall size of the video file. The first thing to go is color resolution. When all the color information is kept in a digital video file, it is referred to as having 4:4:4 color. Depending on the HD recording format, color info may be reduced to 4:2:2 or 4:2:0, and the human eye doesn’t readily discern the difference. 4:2:2 color is an acceptable compromise for most work and is better than 4:2:0 color. Next, some formats actually reduce the horizontal resolution of the signal before compression. HDV reduces 1080 HD video from 1920 x 1080 to 1440 x 1080 pixels, while DVCPRO HD reduces the signal down to 1280 x 1080! The average viewer may not miss the extra pixels, but for broadcast work, it is preferable to maintain full-raster HD whenever possible. After reducing the color resolution and possibly the horizontal resolution as well, the remaining signal is further compressed, with MPEG-2 used for HDV and XDCAM EX, or H.264 for AVCHD formats. Compression uses a complex mathematical formula to get rid of redundant info in the video, reducing file size. If a large part of a scene has blue sky for instance, each of the blue pixels doesn’t have to be represented individually – they can be lumped together, as in "this whole area is blue". That’s a greatly simplified explanation, but that is basically what happens with compression. While the casual viewer may not notice that the color space is reduced or the image compressed, your editing software certainly will! While color grading, you may encounter banding in the blue sky, where the shade of the sky changes in large steps rather than finer gradations. For green screen work, you may have a hard time getting a clean edge on your key to separate the talent from the background. For instance, a Canon 1080i HDV camera might have a 1920 x 1080 image sensor, but only 1440 x 1080 pixels get recorded to tape, and that’s after the color space is reduced to 4:2:0 and the entire image is encoded to lossy Long-GOP MPEG-2 at a data rate of just 25Mbps.
Recording direct from the live camera to the computer using the MXO2 Mini not only provides a higher quality, but will also save you the time normally required for ingest of material from the camera tape or memory card. It’s important to realize that the higher quality uncompressed feed from the camera’s HDMI output is only available live during the shoot. Once material is recorded in the camera, any video played out the HDMI port has already been compressed at that point. I should also note that the MXO2 Mini is capable of up, down and cross-convert on capture, so maybe you’re filming with a 720p camcorder but need to deliver 1080p. Just set up the MXO2 Mini to convert the incoming video using the 10-bit dedicated hardware scaler to record as full-raster 1920 x 1080 to your hard drive. Besides its flexible capture options, the MXO2 Mini also provides an HDMI output for LCD monitoring while editing, and includes a color calibration utility for reliable color grading even on inexpensive displays. Analog i/o is also included, and the MXO2 Mini with the MAX option provides greatly accelerated H.264 encoding. Whether in the studio or on location, Mac or PC, laptop or desktop, the MXO2 Mini can increase the quality of your productions and offers flexible workflow options to help you get the job done – on a budget you can live with. HD to DVD Workflow for Matrox RT.X2
HD video has been around for more than a few years now, and HD editing has been supported for a couple of generations with Premiere Pro. One would assume then that all the kinks have been worked out regarding the HD editing workflow, especially with the latest release of Premiere Pro CS4. Yet for all its power and rich feature set, CS4 is still lacking in one fundamental area – it can’t do a decent export of HD material to DVD! Whether moving to HD shooting by choice, or by necessity of replacing aging SD gear, more and more videographers are shooting HD video today. With the slow adoption of Blu-ray by the public, DVD is still the delivery format of choice for most productions. Exporting a standard-definition MPEG-2 file for DVD from an HD project requires that the video be downscaled from HD resolution to SD resolution, and Premiere Pro just doesn’t handle the conversion very well at all. The resulting DVD video will look jaggedy, almost like it has a reversed field order, with horizontal lines flickering and an overall look of low-resolution. The viewer may not be able to say exactly what’s wrong with the image, other than "it just doesn’t look right." There are workarounds for Premiere Pro users involving 3rd-party applications and scripting, but Matrox provides an easier solution for RT.X2 users by doing realtime downconversion from HD to SD in hardware. In the CS4 Sequence Settings (or CS3 Project Settings), users can change the Master Output from 1080i to NTSC and the analog output from the RT.X2 breakout box can then be displayed on an SD display. 1080i video downscaled to NTSC looks very clean on a standard CRT display, meaning the Matrox hardware conversion works well.
RT.X2 users can benefit from this realtime downconversion to bypass the inherent scaling issues in Premiere when creating DVDs from Matrox HD projects. When you’ve completed the editing of a Matrox 1080i project and you are ready to export to DVD, follow these steps for good results.First, Export the HD timeline as a Matrox standard-definition .avi file. The Matrox MPEG-2 I-Frame HD codec is the default codec and needs to be changed. In the Export Settings dialog, change the compressor to "NTSC Matrox MPEG-2 I-Frame", then change the Pixel Aspect Ratio from "1.333" to "D1/DV NTSC Widescreen 16:9 (1.2)." Optionally, you can bump up the data rate for your .avi file using the "Configure" button. The default setting of 25Mbps looks good, but I often just use 30Mbps to give it a little extra boost. This Export process uses the Matrox hardware to downscale the HD video to SD, using the high-quality Matrox codec which has a 4:2:2 colorspace. HDV video uses 4:2:0 color, so be sure to choose the Matrox MPEG-2 codec and NOT Matrox DV, which is 4:1:1. The 4:2:2 codec will maintain more of the color fidelity when converting from HD to SD, and ultimately to DVD. Exporting the HD timeline to the SD avi should be a faster-than-realtime process, so not much of a delay in the workflow. Once the file is exported, open a NEW Matrox DV widescreen project, Import the new video file and place it on the timeline. You can preview it and should find the quality to be very good. From the timeline, you can then use the Matrox Media Encoder (CS3) or the Adobe Media Encoder (CS4) to create an MPEG-2 for DVD file with good results. Be sure to check the 16:9 aspect box in the encoder to match the aspect of the original footage. Since Matrox did the actual conversion from HD to SD, the new file can be rendered to MPEG-2 as you normally would for SD files without quality issues since Premiere is not doing any scaling on the video. I’m confident that you’ll find this workflow to be a quick and easy way to achieve good results on your next HD to DVD project using the RT.X2. Making Money with Dance Recitals
I’ve been videotaping dance recitals for 15 years now, and it’s proven to be a lucrative segment of the event video market for me as owner of Digital Vision Productions. Parents spend a lot of time and money sending their kids to dance lessons, and it all comes together once a year at the big recital held at the end of the season, usually in May or June as school lets out for summer break. Parents, grandparents, aunts and uncles all come to the theater to view the performances, and it’s a big deal. Younger performers might only be in one dance, with the 3 year-olds dressed in little bumblebee or kitten costumes, but those few minutes on stage are precious and will be cherished for years to come, provided they are captured on video. Older, more experienced students might take part in several dance numbers, with the best students getting their own solo performances to "show their stuff". Parents often bring their own camcorders and attempt to capture the event, but the auto-exposure of consumer camcorders will typically ruin stage shots by overexposing the performers so their faces become unrecognizable white blobs. The hapless parents don’t know how to override the auto controls to correct this issue and end up with junk footage. Having to run a camcorder also keeps the parents from "being in the moment" and truly enjoying the performance. Most dance studios will offer DVDs of the recital, though the videos vary greatly in quality and coverage, with many being very amateurish. This provides an opportunity for professional videographers to step in and offer a superior product. When I was first asked to videotape a dance recital back in 1994, I had just started taping weddings and was fairly new to the business. I accepted the job and it actually went pretty well. I used a single Hi8 camera, and would start each act on a wide shot, then would smoothly zoom in for a head to toe shot and slowly pan across the performers so their faces could be made out, then I’d return to the wide shot to show everyone again. This worked well enough for a couple of years, and as my business grew, I added a second camera so that one camera was always wide showing all the performers, and the other camera would do close-ups and I could switch in post between the two. While I was doing nice work, with good exposure and framing and smooth motion, some parents were complaining that during the close-ups they were then missing their own child who might be out of the frame for several seconds. They didn’t want to miss a single second of their child’s performance, but if I used only a wide shot the entire time, it would be impossible to even tell who was who from a distance. By the late 1990s, I had picked up a second dance school and had switched to miniDV cameras and nonlinear editing and developed a new technique for shooting and editing my dance shows. I still used the two-camera close-up and wide shooting style, but rather than switching between the two, I combined both images using picture-in-picture and split-screen techniques.
While this did require more work in post, I immediately started getting great feedback from the parents – they loved it! Sales really took off after using the new editing style. If there are kids lined up across the entire stage, by the time I pull back far enough to get everyone in the frame, individual faces become unidentifiable. Meanwhile, there is a LOT of empty space in the frame, showing just background.
Rather than centering the talent, I frame them in the lower third of the screen, leaving the entire top two-thirds of the frame wide open for a PIP or split view from the close-up camera. By combining both images, parents can see their child at all times on the lower portion of the screen, and are also guaranteed some great close-ups as well. It’s a win-win situation for the viewers, and everyone is happy! When using this method, proper framing while shooting becomes more critical to minimize or eliminate repositioning during editing. If shot properly, I can simply do a split-screen effect and not have to reposition either video source in post – they line right up! I use Adobe Premiere with the Matrox RT.X2 hardware, which eliminates rendering, so I can do PIP and split-screen effects along with titling and color correction, with no waiting. One of my dance studios now has 4 shows, each almost 3 hours long, so you can imagine how much rendering time is saved when considering that almost every act uses some sort of PIP or split-screen view. Solos are of course a single close-up view, and some acts are so dynamic with everyone constantly moving about that it’s impossible to do any close-ups, otherwise I use the dual-view religiously and have never had a single complaint. In fact, parents go out of their way to tell me how much they love the DVDs because they never miss a thing! Before each show, I also get access to the dressing rooms/staging areas to get some fun shots of kids getting their makeup and hair done, waving to the camera, warming up, etc., and this is also well-received and asked for. For the guys reading this, just be sure to have a "stage mom" verify that everyone is dressed and announce your entry to avoid any surprises! Camera Setup I set the white balance to the indoor, or incandescent, preset since lighting will be constantly changing during the performance. By using the indoor setting on both cameras, they will match and I can always color correct in post if necessary. (See my April 21st article,"Consistent White Balance for Live Events" for information on color correcting in post.) It’s mandatory to manually control the exposure settings, since the spotlights on the dancers against a darker background will usually cause the faces and lighter costumes to completely blow out when using auto exposure. Use the zebra stripes function on your camera so you can identify hotspots and stop down the iris as necessary. If you get back to the studio and find that all the faces are overexposed, it is too late. The recitals I cover have loud, high-quality sound systems in the front of the auditorium, and I’ve gotten good audio by simply using on-camera microphones. Some videographers like to place a flat PZM mic on the stage to better pick up tap shoe sounds, but this would be just part of the overall mix and not the main mic. If using camera mics, make sure there isn’t a fidgety kid squeaking his chair or digging into a candy bag near you, as these sounds will be part of the production!
However, wiring your camera directly to the sound board, recording only the CD tracks played for the dances, might seem like an ideal solution, but it is not. There will be no applause, no tap sounds or ambience of any kind recorded and it will do nothing to enhance the video. Editing Once the clips are synched and the audio level set, I then go through and set In and Out points and use the Extract function to remove the dead space between acts when the curtain is closed. I also color correct if necessary, then add my PIP and split effects and titling. The end of an act will fade to black and silence, then I fade up a simple white on black title screen, and fade into the next act as it begins. The result is that when creating chapters for each dance act on the DVD, the chapter mark is right before the title fades up. No matter which chapter the viewer jumps to from the menu, there is no abrupt sound or picture coming in, it always starts on black then moves right into the title followed by the dance number. If the viewer skips through the disc with the "Next" button, it works very smoothly and cleanly. DVD duplication and printing is handled in-house for quick turn-around and quality control, as well as cost savings. If you do just a few events a year that require a lot of DVDs, a duplicator-printer setup can pay for itself very quickly. I use the standard black Amaray-style DVD cases just like the Hollywood DVDs and print my own inserts, normally scanning the recital program and using that existing artwork as the basis of my insert design, quick and easy. Sales and Marketing I come in as an independent contractor and handle the whole job. I take care of making the order forms available, and parents can mail me the form with their check, or they can just phone in a credit card order, which a large number do take advantage of. The studio in turn gets a certain number of free DVDs for their staff and families as a thank you for the opportunity to cover the event. Some producers will determine what they need to make as a minimum on the job, and will prepare a proposal that may require the studio to guarantee a minimum number of DVD sales, after which there may be a reduced rate for additional copies that allows the dance studio to make some money. When getting a studio to guarantee minimum sales, they will normally handle the sales and pay you for the DVDs themselves. In any case, get it all in writing with the studio to avoid issues later on in case there are any issues or disagreements as to who owes what. I’ve been getting $30 per DVD in the Midwest, while I’ve heard of producers in other markets getting as much as $45 per DVD. It may help to put up a table or booth in the lobby at the recital where people can view your work and place orders. I’ve been with my dance studios for so long that everyone knows me and I just make sure that plenty of order forms are available both at rehearsals and at the show. You might wish to offer a discount when customers order two or more different shows to spur additional sales. I do have a lot of post-production time setting up the multiple views and titling the acts. If you have the experience, equipment and crew to properly handle live-switching the event, this could definitely increase the profitability of the job. One method would be to record the live switch, as well as having tape in the individual cameras, and then in post you can just do clean-up up editing as necessary before duplicating. Another more aggressive tactic would be to live switch directly to a DVD recorder, and as soon as the program ends, start running copies on a DVD tower using pre-labeled blanks and make them available immediately to get the impulse buys. If you choose the latter route, make sure you’ve got the procedure down pat, as many things could go wrong. I believe I can always deliver a more polished product by editing in post, but that’s just my personal preference. Many successful event videographers offer live-switched productions and do very well with them. In these hard economic times, it makes sense to diversify your offerings. Maybe you’ve always done just corporate video or weddings, but if business is slow, call those dance studios. In larger metro areas, see if the city park district runs a dance program in addition to the privately-owned studios. I’ve gotten some nice corporate jobs from parents who’ve seen my recital work, so don’t discount the idea. There could be a gold mine in your own backyard, and it repeats (and should grow) every year! The Great Debate - NTSC HD vs. PAL HD
Technically, the title of this article is incorrect, since NTSC and PAL refer to standard-definition video formats. Nevertheless, you may see these terms come up in the various places, so please read on and it will soon make sense. As HD video was first gaining momentum a few years back, many videographers were excited that we might finally be able to have a worldwide video standard that would eliminate the incompatibility issues between the NTSC and PAL video formats used in different countries. In case you’re not familiar with the differences between NTSC and PAL, here's a short history here. In the U.S., the standard-definition video broadcast standard has always been NTSC, which uses 525 lines of video at 29.97 fps (frames per second). In the digital world of the NTSC DV format, popular in camcorders and computer editing applications, 720x480 pixels are used to create a frame of video. PAL video, used in the UK and many other countries, is a 625-line format at 25 fps. PAL DV uses a 720x576 frame size, somewhat larger than the 720x480 of NTSC DV. So, not only is the video frame a different size, but the frame rates differ as well with 25 for PAL vs. 29.97 for NTSC!When video editors need to combine NTSC and PAL footage for various reasons, there must be a format conversion to account for the differences in both frame size and frame rate. It’s more than a minor inconvenience, to put it mildly, and most video professionals would love to see these differences go away. As mentioned earlier, HD video was supposed to eliminate the incompatibility between videos from different countries, since the same frame sizes are used worldwide. For instance, full 1080 HD is 1920x1080 pixels, 1080 HDV uses 1440x1080 pixels, and 720p uses 1280x720 pixels in any country. The problem that arises is that many HD formats still have different frame rates between NTSC and PAL countries. While HD has unified the frame sizes, we are still stuck with "PAL" HD using 25 fps while "NTSC" HD uses 29.97 fps. With interlaced video formats, each frame of video is actually made up of two fields, meaning PAL video has 50 fields and NTSC has 60. This correlates to the electrical systems used in PAL and NTSC countries, which operate at 50Hz and 60Hz respectively – in other words, the video equipment gets its timing from the power source. Even though progressive-scan video uses only frames and not fields, we can still feel the effects of PAL vs. NTSC when looking at 720p video – 720p30 runs at 29.97 fps and is used in countries with NTSC, while PAL users shooting 720p will have 720p25 at 25fps! It seems that the only "universal formats" may be 1080p24 and 720p24, as these will be 24 fps in any country. Note that 24 fps is also the speed of movie film, which may be behind the universal appeal of 24p video. From now on, if you see "PAL" associated with an HD format, it means it uses 25 fps, while NTSC would mean 29.97 fps. While not really correct, these labels continue to be used, but at least you’ll understand the reference when it comes up. So as not to perpetuate the erroneous PAL and NTSC labels as you move into HD production, you should be familiar with proper HD format labels. While the exact syntax may vary from place to place, a typical designation of "1080i30" would equate to 1080 interlaced video at 29.97 fps and "720p24" would be 720 progressive at 24 fps. You will do well to forget about PAL and NTSC labels and pay close attention to frame rates when shooting and editing HD video.
Many HD cameras offer multiple frames rates, and some even offer both 1080 and 720 recording capabilities, so be very careful when setting up the camera for a shoot, whether for yourself or when providing footage for another company. If you choose the incorrect format, it could turn into a hassle as the footage may require conversion which takes time and could also reduce the quality. Sony DV Tapeless Workflow for RT.X2
Tapeless workflows are rapidly becoming very popular because they eliminate the lengthy process of capturing footage from video tape to the editing system hard drive. Video clips recorded to flash media in the camera can be quickly transferred to the editor’s hard drive at faster-than-realtime speeds so he/she can get right to work. In fact, the editor may be able to edit directly from the flash media when a compatible card reader is attached to the edit system, though transfer to a hard drive is recommended. The popular Sony HVR-Z7U camcorder can record DV video directly to a Compact Flash card, but the Matrox RT.X2 hardware does not work with the DV AVI Type 1 files written by the Sony unit. While Premiere Pro will accept Type 1 or Type 2 files, Matrox requires Type 2 files for realtime playback. Type 2 files follow the VfW (Video for Windows) standard, with the audio recorded as a separate file in the DV data stream, while Type 1 files have the audio multiplexed into the video stream. Type 1 files are slightly smaller than Type 2, and perhaps this is why Sony chose to write Type 1 to the flash memory. Sony also makes an optional accessory recording unit called the HVR-DR60 for users of other Sony camcorders having 1394 output. The DR60 records the same Type 1 DV files as the Z7U camera, so RT.X2 users will run into "red lines" in Premiere Pro with these files as well. The fix is to convert the Type 1 files to Type 2 so they will play realtime in a Matrox DV project. The quick and easy conversion method is to use a conversion utility from Canopus, who has for many years provided DV capture hardware for PC editors. The free Canopus DV File Converter software should allow you to quickly find and download this handy utility - you can download it here.
Conversion can be done on individual files, or you can quickly batch convert an entire folder at once. Using the Microsoft DV AVI 2 setting produces files that work in realtime with the RT.X2 hardware, enabling users to enjoy a realtime, tapeless DV workflow. Can I Edit Matrox Projects on Non-Matrox Systems?
The short answer is no, but there are workflows you can use. While there are issues opening a Matrox project on a non-Matrox machine, you can easily go from a Premiere-only project to a Matrox project for realtime effects and finishing work. If you capture DV footage with the RT.X2 and want to edit that footage on a PC that does not have Matrox hardware (Premiere only), you can install the Matrox codecs from the RT.X2 driver disc and you can then work with those Matrox DV .avi clips using a Premiere DV preset. This does not work for Matrox-captured HDV clips with the .avi extension since that codec is hardware-dependent, but there is a way around that – capture your HDV video using the Premiere HDV preset rather than the Matrox preset. The files will have an .mpeg extension, but are still compatible with Matrox projects. In this way, you can capture and rough-cut HDV projects on PCs and laptops having Premiere software only. The project can then be transferred to a Matrox machine via external hard drive. Open a NEW Matrox project using a Matrox preset to match your footage, then go to File > Import and import the Premiere project file of choice. In the clip bin, open the project folder that is created and double-click a sequence to open it and work on it. Matrox effects can now be added and you will have all Matrox features and outputs available just as if it was a Matrox project from the start. Note that Premiere DV clips should also work in a Matrox DV project (no redline), but as with any of the suggestions on this page, I really recommend doing a short test of the desired workflow to make sure it meets your needs and works as expected before committing to an actual project. Projects saved using a Matrox preset might open on a non-Matrox machine, but will open in "Desktop Mode" since Premiere will not recognize the Matrox project preset and effects. Any Matrox-specific effects you had applied will be lost, so this is not a viable option - it’s a one-way trip from Premiere to Matrox. As long as you understand these workflow limitations and pre-plan a little, you should be fine when sharing projects between Matrox and non-Matrox edit stations. Why Does Matrox RT.X2 Use a 720x486 Video Frame Size?
NTSC DV and DVD video both use a frame size of 720x480, but the D1 NTSC Broadcast Video spec is 720x486. The Matrox Axio hardware uses the D1 spec, so to maintain project cross-compatibility between the RT.X2 and Axio platforms for editors using both, the RT.X2 uses the D1 spec. If you capture using a Matrox DV preset, the video IS captured at the standard 720x480 size, so in the Premiere preview window, the DV image is centered with 3 black lines above and 3 below to fill out the 486 frame size. When exporting to DVD, the 6 extra lines are removed so the export is the proper 720x480 size.
For most editing, you can disregard the extra black lines top and bottom, but there are circumstances where some action is required. If you are doing a Matrox Page Curl or any other effect or transition where the black lines are distracting, just use the CROP function to trim them off. CROP is found in most Matrox effects if you scroll down through the effect parameters. You can also apply Matrox Move & Scale just to use the CROP function.
Note that these black lines are specific to standard-definition projects only and do not appear in HDV projects, as HDV is always 1440x1080 for 1080i/p and 1280x720 for 720p video. Consistent White Balance for Live Events
When videotaping live events such as wedding ceremonies, school plays, concerts or dance recitals, the videographer typically has no control whatsoever over the lighting. To make matters worse, the lighting may be constantly changing during the event. A church may have stained glass windows, meaning any entering sunlight may be tinted by the color of the glass. In this case, manually white-balancing the camera may produce good colors, but what happens when the outside light coming in alternates between sunny and cloudy? It can have adverse effects on the white balance. Also, cameras set up at different angles in the church may produce inconsistent colors due to the mixing of electric lighting and window lighting, resulting is mismatched clips when mixing footage from two or more cameras. Stage plays and dance recitals will usually have mood lighting applied, with different scenes having unique lighting treatments to set certain moods. There is no simple way to compensate for all the different setups. Most camcorders allow one custom WB preset, and some now offer two manual presets (A and B), but even two presets will likely not cover the range of lighting you will encounter. You also may not even have an opportunity to test the lighting to set your white balance prior to the event. Many videographers will forego manual white balance and simply set all cameras to the same preset, such as incandescent. While the colors in the recorded video may be off, the idea is that all the cameras will have a matching image and the colors can be corrected in the nonlinear editing suite. Once an appropriate color fix is created in the software, it can be applied to video from all cameras for matching results. I recently did a two-camera shoot of a school play. Some scenes were well-lit, while others were very dark to simulate evening scenes, and many scenes made heavy use of pink gels, giving the scenes an overly pink tint. I simply set both cameras to the "incandescent" WB factory preset, and only changed the exposure during the shoot, leaving the WB constant.
In post, using Adobe Premiere Pro CS3 with the Matrox RT.X2 hardware, I was able to quickly color correct each scene from the close-up camera. I then used "Copy" and "Paste Attributes" to apply the identical effects to the wide camera clips, creating a perfect match when cutting between cameras. There is no possible way I could have attempted changing white balance between scenes during the live shoot. There are certainly many situations where a custom white-balance setting may give the best results if you know the lighting will remain constant for the duration of the shoot. For ever-changing situations as described in this article, your best bet may be to choose a common preset for all cameras and color correct in post. Each situation is unique, and as a video professional you will need to make the call on each shoot yourself. For the play I’m editing, I’m very happy with the speed and ease with which I’ve reached good, matched colors throughout the production. Leaving the white balance alone during the shoot allowed me to focus on composition and exposure, which was enough work running two cameras by myself! The end results speak for themselves.
Apple ProRes 422 codec vs. Uncompressed HD
Apple introduced the ProRes 422 video codec for Final Cut Studio 2 users in 2007. The codec is said to offer uncompressed quality in a compressed codec, but many editors are nervous about using anything less than full uncompressed video to retain broadcast quality. So what is ProRes 422, and how does it measure up against uncompressed HD video? ProRes 422 is a full-raster codec, meaning the video is not scaled down. The full 1920x1080 image is used, unlike DVCPRO-HD or XDCAM, which scale HD 1080 video down to 1280x1080 and 1440x1080 respectively, effectively tossing out a large amount of picture data to save space. Next, ProRes 422 uses a full 10-bit 4:2:2 color space, which provides much better color fidelity than 8-bit color. This makes a real difference when color grading and compositing images. There is simply more color data to work with, and that can eliminate color banding issues by providing more steps in color gradients. ProRes 422 uses a variable bit-rate compression scheme in which complex scenes are less compressed than basic or static scenes, so the quality is distributed as needed to maximize the efficiency of the codec for the best possible image. For 1080i, the ProRes 422 data rate is 145Mbps, and there’s also an HQ setting with a 220Mbps rate. Compared to uncompressed HD video, ProRes files are about five times smaller, using about 20% as much hard drive space per hour. This means smaller, less expensive storage systems can be utilized, making broadcast-quality HD video production more affordable to smaller production houses and independent video producers. ProRes 422 HD video files are so efficient they can be captured and edited on a Mac Book Pro, something you wouldn’t try with uncompressed HD! There are other HD codecs with lower data rates available, but because they are more highly compressed, they take more processing power to encode and decode (play back). The ProRes 422 codec provides a good middle-ground by providing a smaller file size than uncompressed, while providing easy capture and playback on even marginal machines. But what about quality? Review after review by video professionals have consistently rated ProRes 422 quality as "visually equivalent" and "undistinguishable" from uncompressed footage, even after multiple encode/decode cycles. This can’t be said about many other compressed codecs available today. Another important benefit of ProRes 422 is that it allows more layers of Dynamic RT playback. 4 layers of 1080i can be expected, and 720p 24 editors can expect up to 14 layers of HQ footage playback in real time. For reference, a powerful 8-core machine with a video RAID might only play a single stream of uncompressed HD. Even if you don’t normally work with uncompressed video, ProRes 422 can help editors who shoot with compressed formats such as HDV, which is an 8-bit 4:2:0 format using MPEG-2 Long-GOP compression. HDV does not hold up well to editing, so by capturing to the ProRes 422 codec right away, quality will be maintained from that point on, and it’s easier for the system to work with as well. The ProRes 422 codec is supported in the AJA IoHD product, which is a portable capture and playback interface for use with Mac computers. SD and HD video with audio can be captured via a comprehensive set of professional inputs, with the incoming video being converted to ProRes 422 in the AJA hardware and sent to the Mac via Firewire. When playing back ProRes 422 clips from the Final Cut Pro 2 timeline, video is sent over the Firewire back to the IoHD to be sent out any of the unit’s many outputs to various recorders and displays at full quality. Another i/o device for the Mac is the Matrox MXO2, which has similar connectivity to the IoHD, but lacks a hardware ProRes 422 encoder – it is up to the host computer to encode to ProRes on the fly using its processor, so older Mac Books may not be up to the task to capture HD footage. As always, it’s a good idea to not only compare tech specs, but check video forums online to see how devices like these are performing for actual users to help determine which would suit your needs and budget. One last tip – while the ProRes HQ codec is great for video from high-end sources, it may be overkill for formats like HDV. It’s been reported that users are better off to use the standard ProRes 422 codec at 145Mbps with the lower-end HD formats, as there is no advantage to using the HQ codec when starting with a highly-compressed and scaled HD source format. If you’re a Final Cut Pro 2 user and have not tried working with ProRes 422, you owe it to yourself to try it today and see the benefits for yourself. Adobe Premiere Pro Transitions
Adobe Premiere Pro uses a single-track editing style for applying transitions, so to place a transition between two clips, those clips must be butted together on the same track. Older versions of Premiere used a two-track system, which meant the two clips would be on different tracks, with the ends of the clips overlapped. The transition or wipe would be placed on an effects track layered in between the two video tracks, with the transition duration determined by the amount of clip overlap. Since clips in Premiere Pro are placed end to end on a single track, there is no longer any area of clip overlap in which to place the transition. Thus, the end of the first clip and the beginning of the following clips must be trimmed before butting them together, in effect creating some overlap, or extra material, available for the transition to take place in. The transition is then dropped onto the joint between the two adjacent clips. If I want a one-second dissolve between two clips, I would trim 15 frames (one half second) of video off each clip where they meet. This creates one second of overlap, so I can then place a one-second transition where the clips meet. If I decide to lengthen the transition, one or both of the clips would need to be trimmed more to provide the necessary frames of extra video "overlap" for the transition. In the event that you have two clips on the timeline and are unable to drop a transition between them, even though you’ve trimmed the ends, zoom in to frame level ("+" key on keyboard) to examine the area where the clips meet. A small gap of one or two frames may not be visible without zooming in, but would keep you from applying a transition since the clips are not touching one another. If you are coming from Premiere 6.5 or another editing application that used a transition track, it may take a little getting used to in order to remember to trim the clip ends before applying transitions between then. Once you get a handle on the single-track workflow, I’m sure you will find it much more productive to work with as I have.
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