Jump to content
Sign in to follow this  
ginger_marianne

DV or mjpeg encoders?

Recommended Posts

Almost all of the stand-alone encoders I've seen on the market either encode in real-time in mpeg2 or mpeg4 (h.264, divx, etc.). In my opinion, these aren't proper formats for the initial capture, unless somehow the device can capture in these formats in incredibly high quality, which I don't think is possible with today's technology. I usually do some editing that's more substantial than simple lossless cuts. This usually requires me to re-encode one or two times, which would cause a file initially recorded in mpeg2 to take a big hit in video quality. From my experience, even the processor in my laptop has a difficult time handling real-time mpeg2 compression.

I've searched high and low for anything standalone (i.e. not tethered to a laptop) that's not outrageously priced that can encode in mjpeg or DV. With the 32GB SDHC or CF cards now available, you can still record 2 to 4 hours with these codecs at very high quality. And the processing demands with these codecs should be much lower than mpeg2 or mpeg4, with much higher quality.

Currently, I use the Dazzle DVD recorder (aka DVC 100), which attaches by USB to my laptop. It gives excellent quality, but even this isn't a hardware encoder. It still requires the processing power of my laptop, which cuts into battery life. Also, I'm less than thrilled with the software I have to use to record with this device. It doesn't seem to work with any other software except Pinnacle Studio. This is actually the only mjpeg encoder I know of for a laptop. I'm sure there are others, but you would be hard-pressed to find any real specs on any of these USB capture devices online or even on the box. In my experience, the only way to be certain with these devices is to buy it and open the box. It's hard to even figure out if they're hardware or software encoders without opening the box and trying them. And in my experience, hardware mpeg2/mpeg4 encoders produce poor quality results.

I know Canopus makes some DV encoders (hardware encoding I presume?) but they're expensive and they attach to the firewire port. There are two problems with this port. The first is they seem to be being phased out. It may be difficult to find a laptop with this port in the future. The second problem is that the 4 pin firewire port is unreliable in my opinion. The device doesn't have to be unplugged from the port for the connection to be lost. It just has to be shaken a little bit. And, in my experience, you'll have to restart recording if the firewire connection is lost.

So, I guess I'm wondering first of all if there are any:

1. stand-alone low compression (e.g. mjpeg, DV) recording devices, excluding mini DV camcorders

2. USB powered DV encoders.

I know Kilrah had mentioned the PCTV 100e in another thread, and that he could record DV with Virtualdub. But I can't find any specs online. Is this a hardware or software encoder? Can it do DV natively, or is it being re-encoded on the fly by Virtualdub.

3. USB powered hardware mjpeg encoders.

I probably seem picky, but it seems that the state of portable recording should be better by now, especially now that hi-def is becoming the standard. But low definition largely remains the standard for any type of portable recording not involving a full sized camcorder or a bulky laptop and some very well chosen hardware. It doesn't seem to have advanced much in the last 5 years. That seems unusual to me. Maybe I'm just haven't found the good stuff yet.

Thanks again.

Correction: I tried the DVC 100 with the most recent release of VirtualDub, and it worked fine. I was able to use most of the codecs, including mjpeg and DV capture, but I did experience more audio sync problems than when using Pinnacle Studio.

Edited by ginger_marianne

Share this post


Link to post
Share on other sites

I too am looking for something similar, I want to record on board video on to an sd card but find mpeg4 is over compressed.

Worse still if I use it to record the downlink from the ground, any slight glitch gets amplified to the point of making the frame a total loss.

Fingers crossed someone has the answer.

Terry

Share this post


Link to post
Share on other sites
Fingers crossed someone has the answer.

I think the answer has been here for some time now. I think a low compression recorder can be build more cheaply than an mpeg2 or mpeg4 recorder. The problem is probably that the consumer demands long record times, and the average person wouldn't know quality if it hit them over the head. So they keep producing encoders with long record times.

But, then again, I don't see why they can't make a combination mpeg4/mjpeg encoder or mpeg2/mjpeg encoder, so the customer can have a choice.

Share this post


Link to post
Share on other sites

there are a lot of different recorders. Depend of your budget!!

For example, a 640x480 30fps (1500kbps) wich record on SD card, and can power a 5v camera, cost around € 180,00.

But i have also some .mpeg2 recorders, wich record at 720x576 at 8mbps costant!!Smallest more than an hand. (€ 699,00)

A good solution (smallest and cheap) is a GoPro hero wide camera.

I have also a H264 recorder, smallest and works like a dream...

Share this post


Link to post
Share on other sites

If cost is a concern, then your might want to reconsider using an older tape based digital camcorder for recording out at the field? That way you can get good quality with a portable device and convert to your preferred file format at the desktop.

For example, Yb2normal's videos always impressed me with their quality. I recall he used a Sony TRV33 Handycam to record the video from his A/V receiver. These are relatively low cost on eBay (used, working condition). But I see you have excluded DV camcorders in your search. Any reason for that, other than it is older tape technology?

Share this post


Link to post
Share on other sites
If cost is a concern, then your might want to reconsider using an older tape based digital camcorder for recording out at the field? That way you can get good quality with a portable device and convert to your preferred file format at the desktop.

For example, Yb2normal's videos always impressed me with their quality. I recall he used a Sony TRV33 Handycam to record the video from his A/V receiver. These are relatively low cost on eBay (used, working condition). But I see you have excluded DV camcorders in your search. Any reason for that, other than it is older tape technology?

Cost is a concern in the sense that I believe I've seen something that can do what I ask (not sure where though) that went for several thousand dollars. I don't know of anyone that can afford that for a hobby. I'm willing to pay a reasonable price, but I haven't seen anything in the sub-$2000 range (or even the sub-$4000 range to be honest)

MiniDV camcorders are probably the best option, but they were also the best option back in 2001 or 2002. And I don't think DV camcorders with AV in are being made anymore. Also, the tape mechanisms on these cheap miniDV camcorders aren't known for being the most robust. They, for the most part, seem to have a pretty finite lifespan, and the cost of repair is almost always more than the unit is worth. I speak from experience on this. Eventually these will be a rarity, because I think all these units are used at this point. I could be wrong on that.

So, the best option is a used camcorder with a suspect tape mechanism and a ridiculous number of moving parts. I've considered buying some on Ebay, but there are always 2 factors that keep me from doing it. The first is the tape mechanism on most of these is very cheap (seemingly cheaper than previous generation camcorders). Many of them have known bugs that the makers (e.g. Panasonic) even refuse to acknowledge. When you look at reviews on Amazon, many of these people state that it worked for a year, then some error message popped up (like clockwork). My experience hasn't been much different.

I have a thing about longevity of electronics, probably more than most people. For instance, I rarely buy anything with a built-in battery because when the battery dies, that device largely becomes useless (unless you want to hack it and replace the battery). I also dislike lithium ion batteries for that reason. They lose a little capacity every day, and are very particular about being stored with some charge. They may have a higher energy density than NIMH, but they don't last. So, I choose NIMH when I can.

The second factor that keeps me from buying a used camcorder is that while record time isn't the most critical aspect, 90 minutes is still on the low side. Why can't some manufacturer take the same compression engine that's been around since early this decade and record to a simple replaceable laptop hard drive? I would be all over that. And, I don't think it would be that expensive to make.

And, I guess I'm lobbying to a certain extent. I always hope that some manufacturer will see what I write or that I can change peoples' minds about what they're using (to create demand).

Share this post


Link to post
Share on other sites
there are a lot of different recorders. Depend of your budget!!

For example, a 640x480 30fps (1500kbps) wich record on SD card, and can power a 5v camera, cost around € 180,00.

But i have also some .mpeg2 recorders, wich record at 720x576 at 8mbps costant!!Smallest more than an hand. (€ 699,00)

A good solution (smallest and cheap) is a GoPro hero wide camera.

I have also a H264 recorder, smallest and works like a dream...

What type of mpeg2 recorder? I've been considering the Chasecam PDR100 for probably close to 2 years now. It looks like the record quality is very good. But I can't get past the fact that it records in mpeg2. I hate re-encoding mpeg2. The quality loss will probably be substantial. Whenever I do mpeg2 encoding on my computer, I do 3 passes. That's 3 times slower than real-time. If my computer produces the best results that slowly, how can a simple hand-held device do the same thing in real-time. I just don't think mpeg2 or h264 are ideal formats for intial capture for these 2 reasons.

I should point out that both mpeg2 and h264 can be edited losslessly. I use mpeg-vcr and VideoRedo for that purpose with mpeg2. But they're only useful if you're doing simple cuts. If you want to do any real editing, you have to re-encode. Mpeg2 and h264 weren't designed for that purpose. They were designed to be a final result, not an intial capture format.

Can you name the mpeg2 and h264 recorders you're talking about?

Share this post


Link to post
Share on other sites
I know Kilrah had mentioned the PCTV 100e in another thread, and that he could record DV with Virtualdub. But I can't find any specs online. Is this a hardware or software encoder? Can it do DV natively, or is it being re-encoded on the fly by Virtualdub.

Software, with VirtualDub doing the encoding. I would NOT want any hardware encoder to hook to my laptop, as those always introduce a noticeable delay between the arrival of the video signal and the time they send out the encoded result to the laptop who gets a chance to display it. As I want to be able to view the live signal on the laptop's screen for various reasons like a backup in case of failures of the goggles, or just for other people to view, or other non FPV-related activities, I want no delay. Also, hardware encoders are restricted to one format only, while with a software encoder I can choose to use DV, MPEG2, MPEG4 depending on what I see fit for the day's purpose.

I now have a Geniatec C8000T PCMCIA card for my current laptop. I still have the PCTV100e somewhere in case I need it too, but the card is just less bulky and less cabling.

Now to the practical side. I DO have a miniHDV camcorder that has an AV input (Canon HV10, note the newer/current HV20 and HV30 still have it). But even with that, I mostly use my laptop. And even if I can record DV on the laptop - I mostly use the card's software that is very handy to use and does MPEG2 at 6Mbps. Yes DV is a tad better, but frankly - I have a lot of videos originally recorded both in DV and MPEG2 and if I watch the high quality renderings of those today (some examples here), I can't say which one used what. The only thing MPEG2 will have more trouble with is noise in the image due to low reception, but in other cases it's just the same at these bitrates.

What I would not do is encode an edited video in MPEG2 again. MPEG2 works very well as long as the source is perfectly clean (like the raw uncompressed feed it receives from the capture device), but it's very bad at recompressing footage that already has compression artifacts, even barely noticeable ones. I render my final videos using more recent and advanced codecs, mainly WMV9 and DivX. I usually also render to DV and export to tape for best quality archival.

Now to the options robyr1 mentioned - the 640x480 1.5Mbps MPEG4 options are useless if you want quality. I have seen that 720x576 8Mbps MPEG2 recorder, but I think that for 700€ it's just too expensive - maybe if it was DV for that price I'd consider it. If it was solid-state. Some of my applications can't use hard drives and at this price I'd want something that can do all I'd need it for.

I probably seem picky, but it seems that the state of portable recording should be better by now, especially now that hi-def is becoming the standard.

The problem is that apart from very specialised fields like us, nobody needs portable analog video recording nowadays, so people are not developing it, they're rather stopping making them ("all this stuff is so old, and everybody wants HD now anyway"). If at least they were giving us an HD equivalent while they're at it, ok, but as long as they don't we'll still have to do with the old-style stuff... which they don't seem to understand. The target market is so small that nobody's intereted in developing something for it. And if they did the price would most likely be ridiculous again. Hi-def is just helping them to get rid of it as there's no equivalent flow in HD, everything's now digital and "data" transfer of the recorded files via USB, and there's not even a simple way to send a live HD video signal on a cable on consumer equipment (you have to go into broadcast equipment to find a nice lag-free HD-SDI signal on a single cable that would be the digital equivalent of the simple composite wire on analog video).

I think a low compression recorder can be build more cheaply than an mpeg2 or mpeg4 recorder.

Not necessarily. MPEG2 chipsets are so widely used that making an MPEG2/4 recorder is basically assembling a few readily available components together, and voilà, you have a recorder. Using other formats would require some development as the components and software aren't there just waiting for you to use them. DVD players and set-top recorders have become so cheap now because there are just a couple of different chipsets, and everybody uses them, only basically throwing them on a circuit board, changing the startup/background image and a couple of menu options.

Edited by Kilrah

Share this post


Link to post
Share on other sites
Also, hardware encoders are restricted to one format only, while with a software encoder I can choose to use DV, MPEG2, MPEG4 depending on what I see fit for the day's purpose.

Not necessarily. I also have the DVC 170. It's a hardware encoder that does mpeg2, avi divx, and mpeg4 divx. Of course, it does all of them poorly, but it does them nonetheless. Unfortunately, no mjpeg or DV for this device.

Also, my experience with software encoders hasn't been the same as yours, but maybe you're better at picking them or utilizing them than I am. With the DVC 100, I seem to be very limited in the number of formats I can use even though it is a software encoder.

The problem is that apart from very specialised fields like us, nobody needs portable analog video recording nowadays, so people are not developing it, they're rather stopping making them ("all this stuff is so old, and everybody wants HD now anyway"). If at least they were giving us an HD equivalent while they're at it, ok, but as long as they don't we'll still have to do with the old-style stuff... which they don't seem to understand. The target market is so small that nobody's intereted in developing something for it.

There are a few other applications for this technology. There are applications in many types of sports, where people strap a cam either onto a helmet, bike, car, etc. and record that signal directly without any type of preview. But, I do agree, it is very limited at this point. I tried talking to a sales guy at Walmart with regards to a camcorder with AV in (an Aiptek I believe). The guy couldn't seem to grasp the concept of recording a signal from another camera at all. It was like I was speaking Martian.

What I would not do is encode an edited video in MPEG2 again. MPEG2 works very well as long as the source is perfectly clean (like the raw uncompressed feed it receives from the capture device), but it's very bad at recompressing footage that already has compression artifacts, even barely noticeable ones. I render my final videos using more recent and advanced codecs, mainly WMV9 and DivX.

You might be right about that. I've started encoding my captures to mpeg4 AVC/h264. Going from mpeg2 (initial capture) to AVC might yield a lot better results than going from mpeg2 to mpeg2. That might be part of the problem. Nonetheless, I don't think you'll ever convince me that an initial capture should be done in mpeg2, but I'll probably have to get used to it at some point.

Not necessarily. MPEG2 chipsets are so widely used that making an MPEG2/4 recorder is basically assembling a few readily available components together, and voilà, you have a recorder. Using other formats would require some development as the components and software aren't there just waiting for you to use them. DVD players and set-top recorders have become so cheap now because there are just a couple of different chipsets, and everybody uses them, only basically throwing them on a circuit board, changing the startup/background image and a couple of menu options.

Okay. I hadn't considered that.

But aren't DV format chipsets widely available, considering the popularity of the format for camcorders? It seems to me that the number of these DV camcorders made and sold were comparable to mpeg2 recorders, such as those standalone dvd recorders. DVD camcorders are only a fad, and I don't think their sales will compare to that of miniDV. DVD camcorders are probably among the worst camcorders made, and are a definite step down from miniDV camcorders.

I'm just saying I would love to have a standalone DV format recorder on SDHC cards, CF cards, or even hard drives. In my opinion, this format provides the optimal combination of compression, quality, and space for standard definition signals. But I guess I won't hold out hope this will ever happen. It's not like I'm at a loss for capture hardware though. I currently have more capture hardware than I will probably be able to use in the next decade. I actually have a ridiculous number of camcorders, including many miniDV (none with "AV in" at this time). I'm always in a quest for something better though. I'll take a look at the capture cards you mentioned.

Edited by ginger_marianne

Share this post


Link to post
Share on other sites
Also, my experience with software encoders hasn't been the same as yours, but maybe you're better at picking them or utilizing them than I am. With the DVC 100, I seem to be very limited in the number of formats I can use even though it is a software encoder.

Well, the problem is that your card will only work with the supplied software - I got lucky with my PCTv100e, but I've since then learned to stay away from Pinnacle for that reason.

All the cards I've had (that particular pinnacle, an AverTV cardbus a few years ago, another AverMedia card I have now in my desktop PC, and the Geniatec card) are all standard and work with any software that can capture video, and have no delay. That leaves the abilty to choose the programs that work best for each application and format.

Nonetheless, I don't think you'll ever convince me that an initial capture should be done in mpeg2, but I'll probably have to get used to it at some point.

MPEG2 is designed to properly encode a clean source - its main use is DVD, where the production studio will take a perfect output and run it through the encoder - and you'll see a totally fine image on your DVD, I've never noticed bad compression blocks on one in normal conditions. Just don't use it for a bad source.

The other day I recorded a live VJing event with my laptop, had to cut a few parts out and add audio tracks, I re-rendered the result into an equal 6Mbps MPEG2 and the difference was indeed huge, so I ended just exporting the audio tracks, cutting the video with non-reencoding tools, and muxing the items together manually. That took quite a lot of playing with timecodes and offsets, but the result was definitely better.

But aren't DV format chipsets widely available, considering the popularity of the format for camcorders?

Times were a bit different and manufacturers were mostly each doing their own work with relatively specialized custom chips that also contained a lot of the other functions of the camera, rendering them pretty unsuitable for use in other contexts... Today's trend for the low cost market is to have a company who develops a universal chipset intended for use in one type of device, then many different manufacturers will get that chipset and integrate it in their device, with very little need for any other components. Makes development easy for the device manufacturers with pseudo plug-and-play solutions, while the chipset manufacturer will sell huge amounts driving costs down.

I'm just saying I would love to have a standalone DV format recorder on SDHC cards, CF cards, or even hard drives. In my opinion, this format provides the optimal combination of compression, quality, and space for standard definition signals.

I totally agree. At some point I thought it could be a cool thing to try and work on, but I somewhat now think that if I was to start working on video gear, I'd try to look forward and tackle the HD solutions our fields lack instead of investing time on SD gear that is at the end of its life anyway. That might be the reason why nobody's wanting to do it. While that optimal solution doesn't exist, lots of alternative solutions aren't that bad, and not many would want/need the optimal one, so the investment would be difficult to justify.

Edited by Kilrah

Share this post


Link to post
Share on other sites

Here what i mean:

http://www.onboardcamera.it/prodotti.aspx?...ca-9a571bc4f0a0

It's a good recorder, with 720x576 at 8mbps CBR.

the internal Li-ion battery provide to power up the camera too (selecting the output voltage too!) for 130minutes, and also can be powered from an external 12v. After the FB2, is the best/smallest solid state recorder on the market (the FB2 is TOOO expensive right now!).

I use the PDR100 too, but only for cars races.

But if you need QUALITY, the common AVin camcorder or recorders, on miniDV, is the best solution! 25mbps are much more than 8mbps!

There are also some HDV solid state recorders wich record at over 100mbps, but is not very "cheap": € 5000,00!

Share this post


Link to post
Share on other sites

@ Kilrah

So, if I can summarize. What you're saying is that an initial capture to mpeg2 can provide very good quality provided you have a clean source and you don't re-encode to mpeg2. Either do lossless cutting or use one of the more advanced codecs for re-encoding. Stay away from mpeg4 for initial capture?

I also want to add that mpeg4 isn't technically a codec but a container and you could probably use a low compression codec with mpeg4, and get good results. The problem is that mpeg4 is almost always used for highly compressed codecs and may not be suitable for initial capture. I always find it strange when a manufacturer states that a device captures in mpeg4, as if that means anything. mpeg4 is just a container for the codec. The capture codec is what really matters. Are there any mpeg4 codecs that you would recommend for capture?

You actually kind of changed my mind about mpeg2 capture devices. So, what standalone mpeg2 encoders do you recommend? We've talked about the FB2 and the PDR100. Is there anything else?

@ robyr1

The FB2 is expensive. Is the battery actually internal or is it replaceable? I hate internal batteries with a passion. And I don't like proprietary replaceable batteries much either. When an internal battery dies, not only is the device probably useless, but, even if you can use it, it probably has a much lower resale value. And, when I'm out in the field, I like to be able to buy new batteries if I need to.

But other than that, why do you think the FB2 is better than the Chasecam PDR100, which seems more ideal to me (and cheaper)? Is the quality of the capture better?

Edited by ginger_marianne

Share this post


Link to post
Share on other sites
So, if I can summarize. What you're saying is that an initial capture to mpeg2 can provide very good quality provided you have a clean source and you don't re-encode to mpeg2. Either do lossless cutting or use one of the more advanced codecs for re-encoding. Stay away from mpeg4 for initial capture?

MPEG-4 in that case is a set of guidelines defining a way to compress video and a format, without detailing the actual implementation too much. As a result, many popular codecs like WMV9, DivX, Xvid, some Quicktime codecs, h264 and others are actually all built around the MPEG4 specifications, with varying results.

I have compared 6Mbps MPEG2 and 4.5Mbps "high quality" DivX recording on the PC, DivX does give at least similar results to MPEG2 or even a bit better, but that's at the expense of about 4 times more CPU use. My 9" TabletPC laptop with its 1.2GHz Core 2 Duo I use at the field wouldn't be close to being able to cope with that, knowing it uses about 70% of my 3.5GHz C2D desktop PC.

But yes as you said a recorder saying it uses MPEG-4 means just nothing, as there are so many different levels and ways to do MPEG-4 that the result isn't predictable. Due to limited processing power the quality of the encoding on portable devices is often of lower quality than on a PC - an Archos recorder that outputs DivX at 2500kbps will show a lot more compression than the same recorded in DivX on a PC with the same bitrate using "extreme quality" settings. To illustrate simply - rendering the same video on the PC with the same codec and same bitrate, but using "maximum speed" mode rather than "extreme quality" will give very different results - yet that kind of parametrer doesn't exist on stand-alone recorders, and it's not possible to guess what is done and what it would compare to. MPEG-2 quality also varies with each encoder vendor.

So finally the only way to know is again to try.... I know, that's not of much help. What I did on my previous posts was state my experience with the programs and formats I've tried and have experience with - and in this context I'm happy with my MPEG2 solution for general use.

You actually kind of changed my mind about mpeg2 capture devices. So, what standalone mpeg2 encoders do you recommend? We've talked about the FB2 and the PDR100. Is there anything else?

Well, I've never used one, as said above I described my known PC solutions earlier. But the one robyr posted in its above post has interesting specs, I guess it would be worth trying. It seems to suffer from some drawbacks though, I found a manual and it's stated that it can't play back its own recordings, and the files must be run through the supplied PC software before being readable by anything (apparently the video is recorded on the card encoded but without a standard container, and the program just inserts the data into an MPEG2 container). I've already used a recorder with similar workflow, but that was a much larger and non-portable parallel 4-channel hard drive based recorder.

Edited by Kilrah

Share this post


Link to post
Share on other sites
Well, I've never used one, so don't take my word too seriously.

I've seen an unedited capture from the Chasecam. It actually looked good to me. The problem is that the person who did the capture may have used scenery/terrain that was well-suited to the device. Perhaps other locations would yield worse results.

Nonetheless, I've seen many good reviews for it, and it seems to have become the de facto standard in some circles.

I've also seen some good reviews (and some bad ones) for Aiptek camcorders, which do mpeg4 AVC 640x480 I believe. But I've never seen the actual unedited output for one. Without that, I would never consider buying one, even though they are dirt cheap. The reason I say that is that MANY of these same people who give it good reviews often post a sample capture on YouTube and still call it high quality, seemingly not noticing that the YouTube compression has turned the result to crud. People who think anything on YouTube is high quality shouldn't be giving reviews.

It can be like pulling teeth to get a decent review of any of this stuff. Finding an actual unedited capture is like winning the lottery.

Thanks for your help Kilrah.

Share this post


Link to post
Share on other sites
The reason I say that is that MANY of these same people who give it good reviews often post a sample capture on YouTube and still call it high quality, seemingly not noticing that the YouTube compression has turned the result to crud. People who think anything on YouTube is high quality shouldn't be giving reviews.

So true :P

I've tried an Aiptek recorder, and I wasn't happy. Archos recorders are already better even if I'm not a fan either.

Share this post


Link to post
Share on other sites

I just wanted to add a correction. I tried the DVC 100 with the most recent release of VirtualDub, and it worked fine. I was able to use most of the codecs, including mjpeg and DV capture, but I did experience more audio sync problems than when using Pinnacle Studio.

Edited by ginger_marianne

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×