I was wondering if Kdenlive was able to identify 2:3 pulldown in clips? One of my cameras, Canon VIXIA HF100, outputs video as interlaced because it's a consumer product, but they suggest that because of 2:3 pulldown one can extract 24 or 30 frames from it in an editor if it is able to identify the 2:3 pulldown.

From Canon, USA

"In the USA as well as many other countries the Canon VIXIA HF100
camcorder offers a selectable shooting mode which uses true 24 Frame
progressive shooting to give your video a more cinematic look. These
frames of video are recorded by the camcorder and then output via the
HDMI, USB 2.0 or composite terminals by adding a "2:3 pull-down" to
convert the 24 Frames in 30 Frames to be compatible with Televisions and
monitors. This is the same industry standard system used to show
"Hollywood" movies on Television.

Most consumer software packages that support editing AVCHD video are
capable of editing this video in the same way as any other high
definition video. However, some high end customers have requested the
ability to import the video into professional video editing suites and
applying a 2:3 pulldown to the footage which allows the individual 24
Frames to be extracted.

Since the VIXIA HF100 is a consumer class camcorder it does not include
a feature to record 24 Frame video directly. By not including this
feature, frame extraction is somewhat more difficult, requiring that the
editor manually identify the 2:3 pulldown, then the editing program can
extract the 24 Frame video. This process varies from one editing
program to the other and may not be available on all programs. Please
check with your editing software provider to see if this capability is
supported."

Here is the mediainfo:

Format : BDAV
Format/Info : Blu-ray Video
File size : 1.90 GiB
Duration : 16mn 27s
Overall bit rate mode : Variable
Overall bit rate : 16.6 Mbps
Maximum Overall bit rate : 18.0 Mbps

Video
ID : 4113 (0x1011)
Menu ID : 1 (0x1)
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.0
Format settings, CABAC : Yes
Format settings, ReFrames : 2 frames
Format settings, GOP : M=3, N=15
Codec ID : 27
Duration : 16mn 26s
Bit rate mode : Variable
Bit rate : 15.7 Mbps
Maximum bit rate : 16.0 Mbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 29.970 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Interlaced
Scan order : Top Field First
Bits/(Pixel*Frame) : 0.252
Stream size : 1.80 GiB (94%)

Audio
ID : 4352 (0x1100)
Menu ID : 1 (0x1)
Format : AC-3
Format/Info : Audio Coding 3
Mode extension : CM (complete main)
Format settings, Endianness : Big
Codec ID : 129
Duration : 16mn 26s
Bit rate mode : Constant
Bit rate : 256 Kbps
Channel count : 2 channels
Channel positions : Front: L R
Sampling rate : 48.0 KHz
Bit depth : 16 bits
Compression mode : Lossy
Delay relative to video : -67ms
Stream size : 30.1 MiB (2%)

I cannot speak for the backend technology that Kdenlive uses and whether it "knows" about 2:3 pulldown and can "extract" progressive frames from the footage. However, I can say that when I have shot in interlaced formats on the VIXIA and R20 series by Canon, Kdenlive can convert it within a 24p timeline and I have never experienced any interlacing artifacts.

Whether or not it's actually disposing of the excess partial-frames and just keeping the progressive frames, however, I cannot say for sure. I would be willing to bet that that is what it is doing, but maybe a developer would know better about the actual process being used on the backend.

I've shot and edited with the VIXIA series for a few years now and Kdenlive as treated the footage quite well.