Nintendo 3DS Camera

This application allows the user to take/view photos and, since the 4.0.0-7 update, videos up to 10 minutes.

The resolution of the top-screen on the 3DS is 400x240.

ffmpeg -i video.ext -ss 0 -t 600 -y -r 24 -vsync 1 -vcodec mjpeg -qscale 1 -acodec adpcm_ima_wav -async 1 -ac 2 /DCIM/xxxNINxxx/HNI_%04d.AVI

ffmpeg -i video.ext -r 24 -vsync 1 -vcodec mjpeg -qscale 1 -acodec adpcm_ima_wav -async 1 -ac 2 -vf scale=min(400\\,240*a):-1,pad=400:240:abs(ow-iw)/2:abs(oh-ih)/2 /DCIM/xxxNINxxx/HNI_nnnn.AVI

ffmpeg -y -i “video.mp4” -s 960x240 -aspect 2:1 -r 20 -vcodec mjpeg -qscale 1 -vf crop=480:240:0:0 -acodec libmp3lame -ar 41000 -ab 96k -ac 2 “left.avi” ffmpeg -y -i “video.mp4” -s 960x240 -aspect 2:1 -r 20 -vcodec mjpeg -qscale 1 -vf crop=480:240:480:0 -an “right.avi”

ffmpeg -y -i “left.avi” -i “right.avi” -vcodec copy -acodec adpcm_ima_wav -ac 2 -vcodec copy -map 0:0 -map 0:1 -map 1:0 “VID_0001.AVI”

First two lines generate left and right files video, the last line generate the 3D video for the 3DS

Put the file in DCIM\xxxNINxx

The photo gallery implements various restrictions on its images:

• A 4:3 image must have an image resolution of at least 160x120 to appear in the photo gallery. (Minimum image resolutions for other aspect ratios are currently unknown, as are maximum image resolutions for any aspect ratio.)
• Additionally, certain features are only available for valid Nintendo 3DS photographs:
  • The left-eye image’s Exif metadata must specify a camera make of Nintendo, a camera model of Nintendo 3DS, and a software name of 00204.
  • The zoom feature is only available when viewing any image with an aspect ratio which is no more horizontally dominant than 4:3. For example, a 480x480 image will be zoomable due to its aspect ratio, but a 480x288 image will not be zoomable because its 5:3 aspect ratio makes the image too wide relative to its height. All zoomable images are initially zoomed in when viewed in the photo gallery.
  • Each 3D image features a faded black border and can be manipulated with the 3D Focus slider, but only if the image is at least 480 pixels wide and contains a valid 3DS Camera maker note in the left-eye image’s Exif metadata.

Every Nintendo 3DS Camera photo contains a maker note in its Exif metadata. 3D images contain two maker notes - one for the left-eye image, and one for the right - but only the left-eye image’s maker note is used. Two maker notes within the same 3D image may be identical to one another, but they are not guaranteed to be. The maker note of a 2D JPEG image seems to always contain an identical maker note to one of its respective 3D image’s individual images, but which one it is identical to is not consistent.

The maker note consists of two custom TIFF fields that both have a type of UNDEFINED. Regardless of the Exif metadata’s endianness, which the TIFF fields must match, the fields’ contents are encoded in little endian.

The first field, which is identified by tag 0x1100, is 80 bytes long. The meanings of its contents are not known, but the first byte Seems to always have a value of 1. The remaining bytes always seem to have values of zero, unless the photo used a sepia filter, in which case bytes 0x8-0x1a (inclusive) are set. This field can be excluded from the maker note without invalidating the 3DS Camera maker note.

The second field uses tag 0x1101. It is 64 bytes long, although its length can be reduced to as few as 21 bytes without issue.

The photo timestamp is represented by the number of seconds that had passed since the beginning of the year 2000 in the photographer’s 3DS’s time zone.

The left translation number indicates how many pixels to move the left-eye image to the left before scaling it to fit the entire image on-screen without stretching it. It inversely affects the positions of the right-eye image and the 3D Focus slider. The 3DS Camera clamps this value to prevent the image from moving off-screen. This value is zero in 2D photos, though 3D photos can use a value of zero as well.

Take, for example, a 640x480 3DS photograph. The 3DS Camera will scale the photo down to 50% of its original size to fit the top 3DS screen, which is 240 pixels tall. This leaves a gap of 40 pixels on both the left and right sides of the image. If these gaps were resized to match the photo’s original scale, which is twice as large as its on-screen scale, the gaps would be 80 pixels wide. As such, the left translation value can effectively range from +80.0, which will move the image to the left edge of the screen, to -80.0, which will move it to the right edge. Despite this range working as expected for an image of this size, the 3DS Camera’s image gallery does not allow the user to move any photo to the very edge of the screen. For the example above, the maximum absolute value seems to be somewhere within the mid-to-low 50s.

The left translation value can be changed by moving the 3D Focus slider while zoomed in, or by readjusting the photo’s position while zoomed out. This will update the left translation value held in the left-eye image’s maker note as well.

The photo filter(s) value seems to specify information about photo filters that were applied to the image. Some filters seem to use the same values. When filters are not present, this value is 0.