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Video Editing with Sony's MICROMV   (7/2003)

    (Sony MovieShaker, Pinnacle Studio 8, 
        Ulead Video Studio 7)

    by Douglas Dixon

MICROMV Format 
MPEG Issues
Sony MICROMV Camcorders

Sony MovieShaker
Pinnacle Studio 8
Sony EZ Editor
Ulead VideoStudio 7

Prime-Time MPEG
References

Sony's MICROMV format has brought the trend of miniaturizing video equipment to a whole new level. If you thought "Mini" DV tapes and camcorders were small, then this next step was certainly to "micro" -- with 70 percent smaller tape cartridges, and cameras that weigh under one pound. Even compared to Mini-DV camcorders, these MICROMV units are significantly lighter to pack and carry, and small enough skip the camera case and just carry in a coat pocket (www.sony.com/micromv).

            MICROMV cassette

How small is the MICROMV cassette? You can describe it as smaller than a matchbox, or about the size of two quarters, or smaller and thinner than half a MiniDV cassette. That is small, indeed.

As this kind of equipment gets smaller and smaller, however, there comes a point when the trade-offs become too severe, as the LCD screens get too small to view details and the buttons become too tiny to control reliably with your fingers. These really are personal preferences, however, and depend on how the camcorder fits into your hands and with your shooting style.

But MICROMV also introduces another significant trade-off: while these camcorders connect to your computer with a FireWire interface, they do not record digital video in DV format. As a result, they do not interface directly with the wide variety of video editing and DVD authoring tools that can capture and process video directly from DV equipment. Instead, Sony provides its own MovieShaker video editing application with to import and edit digital video. MovieShaker also can convert MICROMV video to other formats (including DV), and convert video files back to MICROMV format to export back to the camera.

This situation improved in early 2003, as Sony introduced new MICROMV camera models. At the same time, new versions of the Pinnacle Studio 8 and Ulead VideoStudio 7 consumer video editing tools were introduced with some MICROMV support. However, you will see from my experience in working with these new products, the MICROMV experience is still nowhere near as smooth as working in DV format.

MICROMV Format

The basic concept with MICROMV was to shrink the size of the tape cartridge in order to also reduce the size of camcorders that use the format. As a result, there is less tape surface in the cartridge than in a Mini-DV cassette, which means fewer bits available to store an hour of video on a tape. As a result, MICROMV requires more aggressive compression of the video data.

        Sony DV and MICROMV Camcorders

DV compresses video to 25 Mbps (million bits per second), which is relatively light compression that gives very high quality video. (If you compare this to using JPEG compression on each individual frame as if it were a digital photo, it's equivalent to compressing 720 x 480 photos to around 100 KB, which still is plenty of bits for great looking images.)

In comparison, video for DVD is typically compressed to around 4 to 6 Mbps using the MPEG-2 format. Since it is highly compressed, MPEG is thought of as a delivery format for the final output of an edited production, while DV is an editing and archival format to save the original video. While DV compression can be done in real time on low-cost chips in any DV camcorder, getting great looking MPEG video for DVD requires significantly more processing and sometimes manual tweaking.

For MICROMV, Sony also uses MPEG-2 format, but at a higher 12 Mbps rate. By increasing the data rate, the camcorder hardware can be designed to still create good-looking video while compressing in real time. You may notice more artifacts such as color fringing than with DV, especially in difficult shooting situation, but the end result is certainly quite good quality. MICROMV also is prone to introducing blockiness at the start of clips and a freeze-frame at the end of each clip, so you will need to be careful to keep the camera running a little longer so you can trim your captured clips.

MPEG Issues

But using MPEG-2 for MICROMV creates other trade-offs. First, the format is incompatible with the wide variety of existing software that can interface to DV camcorders through FireWire connections. After the DV / FireWire interface finally has become ubiquitous and reliable, we're back to square one in requiring special software to interface to video capture hardware.

Second, the MPEG data from the MICROMV camcorders is stored as a MPEG-2 "transport" stream, a format for packaging video intended for transmitting data. Unfortunately, most video editing tools are designed to read MPEG-2 "program" streams, the expected format for packaging and storing MPEG-2 video and audio in files. This means that the MMV files created by Sony's MovieShaker application cannot be read by many video player and editing tools.

Finally, because of the basic nature of MPEG-2 compression, video files in MPEG-2 format are difficult to rapidly search, and not really amenable to frame-accurate editing. Unlike DV, which compresses each frame individually, MPEG-2 achieves much better compression by storing some frames only as differences from adjacent frames. After all, since video frames are shot only 1/30th of a second apart, consecutive frames really do not change very much. MPEG takes advantage of this by analyzing the movement between frames (from a panning camera or motion in the scene), and then describing a frame in terms of background and foreground information from adjacent frames.

MPEG-2 uses an "IBP" compression pattern, with groups of frames starting with a larger I (Intra) frame, compressed individually, followed by smaller P and B difference frames (Predicted and Bidirectional). The B frames actually use difference information from both proceeding and following frames. (MPEG-1 uses a much simpler format, and therefore is easier to edit but obviously does not produce the same compression quality.)

Now imagine trying to rapidly shuttle through a MPEG-2 video stream. You cannot easily jump to a specific frame, since consecutive frames vary wildly in size. If you start trying to decode an arbitrary P or B frame you will end up with a blocky mess, because they depend on previous and even following frames that you do not have available.

Even worse, even if you find the right frame where you want to make a frame-accurate edit, the repeating IBP pattern of the data means that you cannot simply slap in a new frame exactly where you want it. You can either just force all edits to the closest I frame, as some applications do, or you need to uncompress the entire IBP group, edit in your changes, and then recompress the block again. This is not only a lot of work, but continued decompression and recompression of already heavily-compressed MPEG-2 video will quickly cause visible artifacts.

More fundamentally, since MPEG-2 is designed as a delivery medium for playing full-motion video, when you step in slow motion through individual frames the stand-alone I frames clearly look better than the P and B difference frames. As a result, you may not like the visual effect of a cut at the exact frame where you would like to make it.

As a result of all this, while many video player applications now can play MPEG-2 files, they can be sluggish when skipping or shuttling through MPEG-2 files, much less when trying to step backwards. Similarly, many video editing tools really are not designed for MPEG-2 editing. They may import MPEG-2 material, but again they struggle when moving and positioning within the files, and do not support actually editing the IBP data, but instead decompress into a more convenient format.

Working with MPEG-2 really requires an editor that understands and processes MPEG-2 in its native format. Otherwise, your best solution is to transcode from MPEG-2 to a better-supported format like DV to use for editing in your favorite applications.

Sony MICROMV Camcorders

I tried out the Sony DCR-IP55 MICROMV camcorder, introduced in August 2002. It is actually a bit larger than the previous DCR-IP5, introduced in January 2002, which weighed only 12 oz, with battery, and measured 1 7/8 x 4 x 3 1/8". The upgraded features in the DCR-IP55 include 520 lines of horizontal resolution and a 1 megapixel imager for still images (MSRP $1,499). It includes 10X optical zoom, pop-up flash, NightShot mode for dark scenes, and Memory Stick media for still photos and MPEG movies.

                

  Sony DCR-IP5  &               Sony DCR-IP55     MicroMV camcorders

The DCR-IP55 has several interesting design elements to accommodate its small size (15 oz without battery, and 2 3/8 x 2 7/8 x 5 1/8"). Since there is limited room for dedicated buttons on the case, the swing-out 2 1/2" LCD has a touch screen, with both play controls and access to the menus through a tabbed interface. Sony also designed a swing-down handgrip on one side of the cam to make it easier to hold the camera steady. The handgrip covers the tape door, and actually holds the removable battery.

The DCR-IP220 Network Handycam Camcorder has an very different design, with a larger lens barrel and the camcorder mechanism along the side (at 1 lb. 2 oz, and 3 7/8" x 3 x 5 3/8). It has 530 lines of resolution and a 2 megapixel imager (MSRP $1,999).

These cameras include Bluetooth networking technology and can actually take video and still images recorded on the Memory Stick and email or post them to the Internet using a Bluetooth modem.

All MICROMV camcorders include FireWire interfaces, also called IEEE 1394, or iLINK by Sony. The cassettes hold 60 minutes of video. All MICROMV cassettes include a 64 Kb Cassette Memory chip that provides a visual index of the clips on the tape.

Sony MovieShaker

Sony's MovieShaker application version 3.1 ships with the MICROMV camera, and is explicitly designed to support the format and camera features on Windows machines. It imports and exports clips directly from and to the camera, and reads and writes clips to disk in MMV format.

The MovieShaker interface has a center Monitor panel area, with a Clip tray on the left, a Tool panel on the right, and the Product tray on along the bottom. The MovieShaker workflow follows the tabs above the Monitor to progress from Capture to Editing, first importing clips into the Clip tray, then assembling them as a storyboard in the Product tray, applying edits from the Tool palettes for Effects, Text, Transitions, and Narration, and then clicking Export to save the resulting movie.

   

One major advantage of using MovieShaker for importing from the camera is the ability to preview the clips stored on the tape. Click the Scan button under the Capture tab, and MovieShaker will shuttle rapidly through the tape, extract thumbnails for each clip, and display them in the Index tray in the Tool palette. You then can select individual clips and click Batch Capture to have MovieShaker capture them. Or click Dubbing to capture all the index clips from the tape.

You also can use MovieShaker to import and export video from and to the camera, and to convert to DV or another format to process the video using your other favorite tools. The MMV files created by MovieShaker are in MPEG-2 transport stream format, and therefore are not directly readable by many applications. I found that QuickTime Player 6 could import and play some MMV files reasonably well, although it could not handle others. Microsoft Media Player also could play the files, but only after they were renamed to MPG.

When you use MovieShaker to convert to DV format, it warns that the operation is going to take a long time. This is irritating in these days of real-time software DV to MPEG transcoding and DV-based previews, but not much slower than similar applications.

Pinnacle Studio 8

Pinnacle Studio 8, released in June 2002, combines video editing with DVD authoring (www.pinnaclesys.com). It can transcode during capture from DV to MPEG, and can import and edit MPEG-1 and MPEG-2 files. For DVD authoring, Studio can create DVD, VideoCD, and Super VideoCD, supports nested menus, and motion menus and buttons. Studio 8 is available for $99, or bundled with a FireWire card for $129 (MSRP).

   

Studio 8 supports importing video directly from a MICROMV camera, using device control to position the tape from the Studio interface. It also can export video back to the camera, after you have manually positioned the tape and started recording.

As Studio imports the MICROMV video, it converts it on the fly to a standard MPEG-2 program stream before writing the data to disk. Because of this processing, it does not display the incoming video while capturing. The captured video then is stored as a MPG file, which means it can be read and processed by a wider range of applications.

Even though Studio can read MPEG-2 files, it is not a native IBP MPEG-2 editor. Shuttling through a MPEG-2 file during editing was sluggish on my system, so you really need to convert MPEG-2 data to DV before doing any interesting editing with it.

Sony EZ Editor

Studio 8 also is bundled by Sony in its EZ Editor product. The Sony EZ Editor Video Editing Kit for MICROMV cameras includes all the hardware and software needed to hook up to a MICROMV camcorder, including a FireWire (IEEE 1394) PCI card, Pinnacle Studio software version 8 SE, plus a FireWire cable, a MICROMV cassette and a CD-R, for $99 (MSRP).

Ulead VideoStudio 7

Ulead VideoStudio 7, released in February 2003, provides real-time capture, edit and output in a consumer-level video editing tool (www.ulead.com/vs). It adds support for Windows Media and DivX format. For DVD authoring, VideoStudio 7 supports VR format from set-top DVD recorders and can create a DVD from the editing project without needing to first save the output video. VideoStudio 7 is available for $99 (MSRP).

   

VideoStudio 7 supports MICROMV format in that is has a new capture plug-in that can import video from a MICROMV camera and write it to disk in MPEG format. VideoStudio also cannot read the MMV format files created by MovieShaker.

VideoStudio 7 is described by Ulead as a native MPEG-2 IBP video editor, and ships with sample MPEG clips. Unfortunately, VideoStudio hung for tens on seconds on one of my test systems whenever I moved the jog bar to jump around in the file, and still worked fine on another system. Unfortunately, this kind of behavior is still too common under Windows as you load multiple applications on a system along with their support files, and find them interfering with each other to access their preferred interfaces to decoders, encoders, capture devices, and other kinds of drivers.

Prime-Time MPEG

Unfortunately, MICROMV's MPEG-2 video just is not yet a prime-time format for editing with common PC-based tools. Beyond the lack of support and sluggish behavior of video players and editors when moving around MPEG-2 files, you really cannot edit and re-edit MPEG-2 video without quickly causing visible artifacts.

Another issue is that while MICROMV video has shot time information like DV, this data is lost in converting to other formats. And even if you use MovieShaker to automatically capture your video into individual scenes, you then have to manually export each shot into a separate file to import into another application.

In addition, even the captured and transcoded MICROMV video exhibited various problems. Some clips broke up with blockiness or green blotches, especially between different shots when the camera was stopped and restarted. Some longer clips exhibited choppy audio or audio sync problems, sliding more than a second within a ten-minute clip. Other files seemed to end with bad data, as tools like Adobe Premiere 6.5 could play the file cleanly, but hung when trying to transcode the last few frames to DV.

Even with these frustrations in working with the MICROMV format, it still is clear that things are improving and that there are effective options for editing MICROMV video. The cameras are wonderfully light and easy to use and the video quality on the tiny tapes is reasonable. Just be aware that the software side is still limited, and so you will need to experiment with the different options.

Much like getting used to working with such a small camera depends on your personal preferences, working with MICROMV video on your computer also depends on your ability to adapt to the available software tools.

References

Sony - MICROMV
    www.sony.com/micromv

Pinnacle Systems - Studio 8
    www.pinnaclesys.com

Ulead Systems - Ulead VideoStudio 7
    www.ulead.com/vs