Black Hole
May contain traces of nut
I've split this off from an ongoing discussion about iOS file manager apps HERE (click).
The thesis is a comparative study of the various means to archive image files (still and video) originated on an iPad (specifically, in case it matters, an iPad 3 running iOS v7.1) on a Win7 PC, and integrating the files into an existing archive of photos taken on numerous other cameras.
For those unaware, the iPad takes excellent video and passable stills (provided the lens is clean and scratch-free - otherwise the images can be washed out with scattered light in bright conditions).
Internally, image files are either .JPG (still photos), .MOV (video), or .PNG (screen grabs), with file name "IMG_nnnn" where nnnn is a four-digit incrementing number (with leading zeros). Ideally, an archive of the files would maintain the original file name, and preserve the creation time-stamp. Obviously the file naming scheme can only accommodate 10,000 images, so if it rolls over files will need to be stored in separate folders to avoid file name conflicts.
Five methods of copying image files to the PC have been tested:
Dropbox
Video .MOV files (as created by the iPad) are very large, at about 150MB/min, so uploads take a great deal of time unless your broadband is very fast (and upload rates are usually a small fraction of download rates). Dropbox users only get 5GB of online storage for free (more available by paid subscription), so the capacity for video is limited. However, it is straightforward to make the uploads available selectively to other people.
The file names of image files uploaded using the Dropbox app are "Photo" or "Video", followed by the creation time-stamp <dd-mm-yyyy hh mm ss> .jpg, .png, or .mov. The original file name and its creation time-stamp are lost.
RManager
Speed of upload to PC is essentially limited by the speed of the WiFi network. The RManager app provides a view thumbnail and details of the image files available in the camera roll, but translates the file names into its own format: <yyyy-mm-dd hh-mm>.[jpg|png|mov]. The original file name and its creation time-stamp are lost.
Note however that <hh> is in 12-hour mode, with no accounting for am or pm. Note also that the time-stamp resolution is only 1 minute, so it is possible to have image files originated within the same minute or 12 hours apart, resulting in the same file name. In this case, the first occurrence is stored as-is, and subsequent files with otherwise identical names are suffixed "(1)", "(2)", etc.
The current version of RManager has poor local storage management, and fails to release storage when no longer required so can easily run out of buffer and crash the upload. It is best to limit upload batches to no more than the spare local storage per batch, and purge the storage after each batch.
File Manager
Speed of upload to PC is essentially limited by the speed of the WiFi network. Unlike RManager, the File Manager app only provides thumbnails of the image files available in the camera roll, but preserves the original file name and creation time-stamp on the uploaded files. Despite the limitations trying to identify specific image files purely from the thumbnail, File Manager is the preferred means to archive image files wirelessly.
Syncios
This is a PC app that provides file manager type functions on the PC, able to move files on and off an iPad connected via a USB sync cable. Transfers are fast (USB speed), and file names / time-stamps are preserved. Syncios requires iTunes is installed, to use the iTunes drivers. This is by far the best method, especially for video (because of the transfer rate), if the tethered connection by USB cable is not a problem.
Why not just use iTunes? I hate iTunes. Apple nanny state.
iCloud
Uploads to photo sharing on iCloud are limited by broadband upload rates, and when downloaded to PC keep the same file name format but are allocated new sequence numbers, and do not maintain their file creation time-stamp. As such, this method is all but useless for archive purposes.
However: during upload, for .MOV files the iPad performs a conversion to .MP4 with a resulting file size of about 22MB/min, with very little loss of quality. This is a 7:1 compression over .MOV, and takes only one seventh the time to upload. Subsequently the resulting .MP4 can be downloaded to PC and/or iPad, and if the original file on the iPad is deleted the video remains available without occupying so much local storage. It is also a very quick and easy way to produce .MP4, instead of transferring the .MOV to PC and firing up a video encoder.
The thesis is a comparative study of the various means to archive image files (still and video) originated on an iPad (specifically, in case it matters, an iPad 3 running iOS v7.1) on a Win7 PC, and integrating the files into an existing archive of photos taken on numerous other cameras.
For those unaware, the iPad takes excellent video and passable stills (provided the lens is clean and scratch-free - otherwise the images can be washed out with scattered light in bright conditions).
Internally, image files are either .JPG (still photos), .MOV (video), or .PNG (screen grabs), with file name "IMG_nnnn" where nnnn is a four-digit incrementing number (with leading zeros). Ideally, an archive of the files would maintain the original file name, and preserve the creation time-stamp. Obviously the file naming scheme can only accommodate 10,000 images, so if it rolls over files will need to be stored in separate folders to avoid file name conflicts.
Five methods of copying image files to the PC have been tested:
- Upload to Dropbox cloud storage using the Dropbox app, then sync to PC;
- Upload direct to PC as SMB network storage via network (WiFi) using free RManager app;
- Upload direct to PC as SMB network storage via network (WiFi) using free File Manager app;
- Access iPad from PC via USB using free Syncios PC app;
- Upload to iCloud cloud storage direct from photo sharing in iPad native Photos app.
Dropbox
Video .MOV files (as created by the iPad) are very large, at about 150MB/min, so uploads take a great deal of time unless your broadband is very fast (and upload rates are usually a small fraction of download rates). Dropbox users only get 5GB of online storage for free (more available by paid subscription), so the capacity for video is limited. However, it is straightforward to make the uploads available selectively to other people.
The file names of image files uploaded using the Dropbox app are "Photo" or "Video", followed by the creation time-stamp <dd-mm-yyyy hh mm ss> .jpg, .png, or .mov. The original file name and its creation time-stamp are lost.
RManager
Speed of upload to PC is essentially limited by the speed of the WiFi network. The RManager app provides a view thumbnail and details of the image files available in the camera roll, but translates the file names into its own format: <yyyy-mm-dd hh-mm>.[jpg|png|mov]. The original file name and its creation time-stamp are lost.
Note however that <hh> is in 12-hour mode, with no accounting for am or pm. Note also that the time-stamp resolution is only 1 minute, so it is possible to have image files originated within the same minute or 12 hours apart, resulting in the same file name. In this case, the first occurrence is stored as-is, and subsequent files with otherwise identical names are suffixed "(1)", "(2)", etc.
The current version of RManager has poor local storage management, and fails to release storage when no longer required so can easily run out of buffer and crash the upload. It is best to limit upload batches to no more than the spare local storage per batch, and purge the storage after each batch.
File Manager
Speed of upload to PC is essentially limited by the speed of the WiFi network. Unlike RManager, the File Manager app only provides thumbnails of the image files available in the camera roll, but preserves the original file name and creation time-stamp on the uploaded files. Despite the limitations trying to identify specific image files purely from the thumbnail, File Manager is the preferred means to archive image files wirelessly.
Syncios
This is a PC app that provides file manager type functions on the PC, able to move files on and off an iPad connected via a USB sync cable. Transfers are fast (USB speed), and file names / time-stamps are preserved. Syncios requires iTunes is installed, to use the iTunes drivers. This is by far the best method, especially for video (because of the transfer rate), if the tethered connection by USB cable is not a problem.
Why not just use iTunes? I hate iTunes. Apple nanny state.
iCloud
Uploads to photo sharing on iCloud are limited by broadband upload rates, and when downloaded to PC keep the same file name format but are allocated new sequence numbers, and do not maintain their file creation time-stamp. As such, this method is all but useless for archive purposes.
However: during upload, for .MOV files the iPad performs a conversion to .MP4 with a resulting file size of about 22MB/min, with very little loss of quality. This is a 7:1 compression over .MOV, and takes only one seventh the time to upload. Subsequently the resulting .MP4 can be downloaded to PC and/or iPad, and if the original file on the iPad is deleted the video remains available without occupying so much local storage. It is also a very quick and easy way to produce .MP4, instead of transferring the .MOV to PC and firing up a video encoder.