12 Replies Latest reply: Feb 20, 2011 9:49 AM by PieroF
PieroF Level 5 Level 5 (4,275 points)
Hi everybody,
I just bought a new AVCHD camera (Canon HF MF31) that allows me to write files back to its memory (32GB) or to its SD card.

I could easily log&transfer a few test clips to FCE, edit them, but now I'd like to use the camera to play them back to my HDTV (through an HDMI link) as I can do with the camera original footage: this is the only way I guess I can use to watch my HD output, without downconversions to DV, aside from my own Mac monitor.
I tried to Export/Using Quicktime Conversion: MPEG-4 (H.264, etc.), and than copy the file back to my camera... but my camera SW didn't recognizes the resulting .mp4 movie.

Is there a way out ?

Thanks for your help

Piero

iMac Intel 24" 3.06 GHz 4GB RAM - MacBook Pro 15" 2GB RAM (10.4.11), Mac OS X (10.5.8), FCE HD 4 - LaCie d2 Quadra 1.5TB (FW/USB), Canon HF M31 PAL Camcorder
  • skalicki Level 5 Level 5 (4,420 points)
    Hey Piero,

    Unfortunately, not that I know of. You may be able to find a program that encodes your files back into the MPEG4 AVC/H.264 (usually .mts files) that AVCHD uses, but I don't think it's commonly done this way.

    You might look into purchasing something like the [WD TV|http://www.wdc.com/en/products/index.asp?cat=30], which allows you to play video from a USB drive without having to first downconvert to SD.

    Sasha
  • PieroF Level 5 Level 5 (4,275 points)
    Thanks Sasha,
    I know I might use something like WD TV.
    But I'm wondering why the camcorder would allow to write movies to its memory from a Mac or PC, unless there exists some tool to encode them.
    Or maybe this write back feature is just supposed to "restore" movies that were previously saved from the camcorder to the external device. I probably should ask Canon...

    Thanks anyway

    Piero
  • skalicki Level 5 Level 5 (4,420 points)
    If you can figure out the directory structure of your camcorder then it should be possible to find a program that can recompress in AVCHD so you can place the clips back on the camcorder. Still, I'd be wary of doing so as you may somehow corrupt the drive or be forced to reformat it.

    As you said, probably better to give Canon a call before trying anything.
  • Karsten Schlüter Level 7 Level 7 (31,350 points)
    PieroF wrote:
    ... I just bought a new AVCHD camera … that allows me to write files back to its memory or to its SD card. ..


    as I like to say: AVCHD is no video-'format', it is a elaborated file-structure.
    codec in use, inside the mts is a 'plain simple' h.264 - there're tools which strip-off the wrapper and prresto! you get a h.264

    to re-enact such a AVCHD-structure seems to be more complicated - I heard of Windows tools, claiming to do that trick (no Windows here = no idea, wether it is true). I made a few (hobbyist!) tests: the other files, e.g. MPL or BDM, seem to be of paramount importance to make a AVCHD-structure fully functional. I lack the time, skills and motivation, to study the specifications to understand, what's going on; on simple observation, the meta-data stored in the MPL are needed for import with iM or FC/e … if the correlation btw. MPL and MTS doesn't 'fit', the whole structure is kaputt .

    to playback HDef, I recommend a Playstation3 as player (pun intended), you can use it wireless with a Mac, by LAN or transport h264.mp4 by stick. My workflow here is: Export as h.264.mov, 25fps, 720p (=my cam is 720p), 3-5.000 kBit/sec = superb quality. for usage on my son's PS3, I quickly re-wrap mov-to-mp4 (PS3 doesn't like mov out-of-the-box) by using Streamclip, that is a <3sec process; then on a stick, into PS3 - crisp!

    or the famous WD TV HD (mini, live, … comes in many flavors), which reads hfs-formatted drives - you have to export and save your projects anyhow on some drive, SDcard isn't meant for longterm storage …
  • PieroF Level 5 Level 5 (4,275 points)
    Hi Karsten, thanks for your suggestions.

    In fact I'm now learning some more about AVCHD live (Wikipedia has a very good article about it), and I understand that I probably was naif when thinking I could easily playback my final movie to the Flash camera as I was used to do with my older miniDV camera.

    From what a learned till now I'd still expect some converter or authoring tool on Mac should eventually be able to create such AVCHD folder structure. It should be no such challenge if you have the specs, and in any case it should be basically the same standard as Blue-Ray...

    Anyhow in the meanwhile I'll try some HD Media Player...
    (I don't have Playstation3 unfortunately)

    Piero
  • Karsten Schlüter Level 7 Level 7 (31,350 points)
    PieroF wrote:
    … I don't have Playstation3 unfortunately …


    I do have a 10y old son - I assume , kids nowadays are born with such devices, me 'Generation Pong', I have NO clue to handle a PS-controller with its zillions of buttons ...

    The main advantage of the Sony: it is a BluRay Player, it has a built-in 120 ( ? ) GB HDD, to store pics, music, video local, it has a built-in 'Airport'/WLAN, with a 30$-SysPref-file you can access your iTunes Library, incl. a cover-flow-ish interface … 

    … and it is video-game-machine. Games like +Assasins Creed+ offer breath-taking graphics! I was in the TV-business, when first 3D graphics appears (silly 'chrome' logos etc) … and now, you get it 'live' - awesome!

    oops, getting off-topic ........

    ---------

    havent't found a good source describing file-struture of AVCHD … and it's beyond my skills, although highly interesting!
  • MartinR Level 6 Level 6 (14,835 points)
    Hi Piero,

    Blu-ray and AVCHD are very similar but there are subtle differences in their folder structures and I suspect also in the associated index, playlist and clip information files. There is a standard AVCHD folder structure (you can find on Wikipedia) ... however I have seen a number of camcorders with non-standard AVDHD folder structures. You could look at the contents of the SD card from your camcorder to see what folders it uses.

    However, you would also have to be capable of generating the associated clip info, playlist, index & thumbnail files. It's not just a matter of creating the H.264 video files. Of course the camera knows how to do this when recording from the lens or analog input. If you could discover how to do it, you could write directly to the SD card without having to connect to the camera.
  • PieroF Level 5 Level 5 (4,275 points)
    Hi Martin,
    I gave a look to the folder structure. The structure itself is quite simple (at least in the few examples I checked from my camera).

    But as you say, the main difficulty is to build the correct contents for the indexes and playlists. Unfortunately they are not in text format: if they were text files I could study them and with some patience and luck I would probably be able to "reverse engineer" them. Instead they are in binary form of some kind, so without the appropriate tools it's virtually impossible to rebuild them. In addition I fear also the .MTS media files are also special in Canon (MPEG Streamclip claims to be able to read and convert them, but in fact I wasn't able, and its author seems unreachable by e-mail...).

    Since any Blu-ray authoring tool would do something very similar to what I'm looking for (given the similarities between their folder structures) I'd expect this problem already addresses and hopefully solved.

    Thanks for all your help

    Piero
  • MartinR Level 6 Level 6 (14,835 points)
    Hi Piero,

    You said, +" ... I'd like to use the camera to play them back to my HDTV (through an HDMI link) ..."+

    You appear to have the same 24" iMac and 15" MBP as I do. They both have a miniDislayport output for a second display. You could use the +Apple miniDP -> DVI adapter+ coupled with a +DVI -> HDMI cable+ to view videos on your HD TV. I use this setup to watch Netflix on my HDTV, both standard def & high def.

    There are also some direct +miniDP -> HDMI cables+ on the market now. Monoprice.com has them in different lengths.

    (Note, with both approaches you will have to make a separate audio connection, since audio is not implemented over the miniDP/DVI/HDMI in these Mac models.)
  • PieroF Level 5 Level 5 (4,275 points)
    Thanks for the suggestion.
    Yes I have the miniDP port but I have to purchase both the cable and the adapter. I'll check on that.
    I guess this way I will share the full Mac desktop with the HDTV, so in order to watch a movie I should configure the 2 monitors side-by-side (not duplicated) and run QT Player on the HDTV monitor at full screen.
    With this setup I would get the same picture quality as with a WD TV ?

    Piero
  • MartinR Level 6 Level 6 (14,835 points)
    I use extended desktop mode in order to take advantage of the full resolution of the HDTV. If you use mirror mode you are limited to the resolution of your iMac or MBP display.

    Just move your viewer (QT Player, DVD player, browser, etc.) to the extended desktop.

    FYI:
    • If you use your MBP for this, you should enable the discrete graphics processor for better performance. The setting is in Energy Saver preferences.
    • If your dock is normally on the right side of your screen, it may disappear when you go into extended desktop mode. Just reposition it to the bottom or top of your screen.
    • I would expect the same picture quality as from a WD TV.
  • PieroF Level 5 Level 5 (4,275 points)
    Thanks Martin,
    I used your suggestion and I bought a MIniDP to HDMI converter, and connected my iMac to the HDTV.
    This seems to work pretty well, even though my iMac is old enough not to output both video and audio on the same HDMI port... Anyway no big issue: I use a separate audio minijack port on both my iMac and my HDTV.

    Now I have a different issue, about interlacing artifacts on my HDTV, but I'll open a new post for that

    Piero