Adobe raw processing of images with the lowly T4i shows the same thing.
Testing the camera at Best Buy, I shot RAW+JPG images and did a couple during a video. The JPG from the camera is full-width but cropped vertically to a 16:9 aspect, while the CR2 file appears to be full-resolution—the thumbnail shows more data on top and bottom, and Picasa can see all the data, albeit with a pinkish tone, but when opening in ACR, the image is cropped like the camera-JPG is.
The issue appears to be a design choice by Adobe, to only produce results that are consistent with the size of the camera JPG, rather than ignoring what the camera does and producing results from all the camera-raw data in the CR2 file. If Adobe had chosen the other way as the only way, then some people who shoot stills during video and had them come out a different aspect ratio might complain how it was different than the camera does with JPGs. My choice would be to have stills-during-video have a user-selectable processing choice of whether or not to use the camera-JPG aspect ratio in the Adobe Raw Engine or to use the full sensor data. A simple “use video aspect” or “use full sensor data” checkmark, perhaps in the crop area or the camera calibration area would work for the case under discussion. It would be grayed out or unseen for almost all camera raw processing and only be applicable to stills shot during video on the newest cameras. Perhaps with time the situation will be more common and Adobe will be more flexible, instead of making an arbitrary decision that limits the people who want it the other way.
I remember one other situation which had an in-camera setting carry over to the raw-processor that really didn’t need to: setting B/W in some cameras would cause where ACR to only allow editing of the image in B/W mode even though the sensor data is still multi-color Bayer filtered.
In 2005 Thomas Knoll wrote a utility "DNG Recover Edges" to recover "all of the pixels that any supported digital camera records, whether it's hidden edges or intentionally cropped formats." Described in a Luminous Landscape article:
Current links (link in that article does not work now):
I've used it to good advantage a few times.
This utility works great, but it will forever change your DNG file to the new dimensions, so if you want to retain the original, make a copy before dragging and dropping your DNG file onto the utility.
I just tried this out on a full frame D800 file where my composition was ever so slightly off and added just enough image pixels to improve the composition - image went from the standard 7360 x 4912 (36.2MP) to 7378 x 4924 (36.3MP) with the DNG file growing by 730k. Cool tool to have in your toolbox