If you missed our webinar on June 22, you can view the recording in its entirety below or here.
Your case involves video evidence from a CCTV system. You’ve received the files—perhaps .irf or .exe, or another filetype—and you’re able to double-click and immediately launch a video player to view them. Perhaps the player even allows you to press a button to export images. All systems go: time to begin your analysis.
Unfortunately, it’s not that simple. In fact, it’s quite likely that there are some significant issues with the video player that can, and probably will, cause problems with your analysis right from the start.
If you’re unable to rely on correct playback, you’ll be dealing with potentially inaccurate evidence that leads to missing key details, misinterpreting events, and potentially jeopardizing your case.
Let’s take a look at some common problems with proprietary players and how to combat them.
What’s Wrong with Proprietary Players?
We don’t always receive video files in “normal” formats like .mp4 or .avi that can be straightforwardly played with common Windows video players like VLC.
Sometimes with these less friendly filetypes, we’re able to launch the video and play it, but only in a proprietary player. For example, this .irf file opens within the manufacturer’s custom player, displaying a view of 16 cameras that we can drill into one by one:
Playback from a manufacturer’s proprietary player with 16 streams.
How can we be confident that what we’re seeing is playing back correctly, and giving us accurate evidence?
Let’s look at what we can actually do with the video. In this case, the size of the player cannot be changed or resized in any way. The only available controls are play, pause, stop, and advance.
The player displays the video at 648×526 pixels, and includes an export option. However, the export option only takes single frame snapshots at a dimension of 704×480. There is a mismatch here, so which option is correct?
Without diving into an explanation of analogue vs digital signals, a frame dimension of 704×480 is very common, whereas a dimension of 648×526 is quite odd. This means it is very likely that our BMP images are “more correct” than the player is displaying. Subsequently, screen-scraping the video as it’s displayed in the player would capture images with the wrong dimensions, creating flawed evidence right from the start. That said, the export option only produces still images—and manually exporting each image frame by frame would be a cumbersome process that would take countless hours.
iNPUT-ACE solves for these all-too-common issues.
Using INPUT-ACE, we can load raw videos into the Interrogate tab and easily and accurately view them.
Video loaded into Interrogate on iNPUT-ACE.
More importantly for our purposes with this case, we can see the timestamp extracted directly from raw data, export images, make clips, and turn all video streams into an asset that we can use in court without changing any of the visual evidence.
Creating a basic iNPUT-ACE workflow that corrects the frame rate in all 16 .irf streams and creates playable .mp4 files.
Let’s take a look at a couple of cases in which iNPUT-ACE’s Workflow functionality does what we need when proprietary players can’t.
Case Study: Inaccurate Image Exports from a Proprietary Player
We have an .exe file to analyze, a common file format that in this case uses a player with two separate camera angles.
Upon launch, the proprietary player produces an uncommon size format, and the window is unable to be scaled. The frame dimensions are not an accurate size for the actual pixels stored in the file, so simply taking screenshots would produce incorrectly sized images.
But we do have another option within the proprietary player called: Save as Image (Actual Size). This option saves a .bmp that looks roughly accurate upon first glance, but before moving forward, let’s compare the same frame in iNPUT-ACE.
Comparing images. Left – Proprietary Player’s Image export, Right – iNPUT-ACE’s image export
By toggling back and forth between these two images, noticeable differences arise.
First, the player-exported .bmp includes a border around the image, which means we’re missing pixels from the original video—not a good sign.
But more significantly, the image is interpolated, and has duplicated a line of data in two different spots. During export from the proprietary player, a horizontal line was added across the image that was not in the original video.
Left – duplicated line from the proprietary player that did not occur in original video file, Right – iNPUT-ACE’s accurate image
This extra line of information can have a serious impact on cases that involve things like:
- Height analysis
- Speed analysis
- Analyzing the shapes of objects
- Photographic video comparisons
- And more
Another example covered in a recent two-day iNPUT-ACE course centered on a player that created problems with RGB values in a video file.
The RGB color model uses values from 0 to 255 for each color value in the image. Some proprietary players, like the one in question in this case, don’t show the full 0-255 range of values; those on either end of the spectrum are clipped, so low-end and high-end values essentially disappear. If we start from an image with these values missing, we can never get them back.
Using iNPUT-ACE instead of the proprietary player, we are able to look at the raw image.
Comparing images. Left – Proprietary Player’s Image export, Right – iNPUT-ACE’s image export. Note the upper-right hand portion of the image as an example of the loss of clarity in the proprietary player.
By comparing the player’s image to the raw image from in iNPUT-ACE, it’s evident that the player was clipping the RGB values. Once we’re missing those values, we would never be able to clarify the footage to its full potential. If we need to clarify the image, we would get better results if we worked from the raw file in iNPUT-ACE.
Starting with evidence exported directly from the player would put us at a grave disadvantage, whereas iNPUT-ACE provides clear, accurate, and reliable evidence to use throughout the case.
iNPUT-ACE reads hundreds of proprietary video formats, and solves issues common to proprietary players with its simple drag-and-drop interface that protects evidence from the start. Ready to begin? Contact us for an iNPUT-ACE trial.
If you’re interested in advanced iNPUT-ACE training, sign up for one of our two-day classes here.
For more detail, instruction, and five additional case examples, please view the full webinar here.