# Performance Evaluation of rPPG Approaches with and without the Region-of-Interest Localization Step
## 2 Materials and Methods  
### Data Sets  
We used three publicly available data sets in our study: _Public Benchmark Dataset for Testing rPPG Algorithm Performance_ (hereinafter PBDTrPPG) [35], _LGI-PPGI-Face-Video-Database_ (LGI-PPGI-FVD) [36] and _Pulse Rate Detection Dataset_ (PURE) [30].  
PURE [30] consists of 59 lossless compressed one-minute-long facial video recordings (recorded at 30 fps and \(640\times 480\) pixels per frame) of ten subjects (eight males and two females) in sitting position during six different controlled scenarios (resting with no intended head motion, talking, slow head translation of 7% of the face height per second, fast head translation of 14% of the face height per second, small head rotation of approximately 20 deg, and large head rotation of approximately 35 deg) and reference pulse waveform signals recorded with pulse oximeter at the sampling rate of 60 Hz. We used all video recordings from the data set and divided them into four groups: resting (10 recordings), talking (9 recordings), head translation (20 recordings), and head rotation (20 recordings).  
LGI-PPGI-FVD [36] consists of 100 uncompressed video recordings (recorded at 25 fps and \(640\times 480\) pixels per frame) of 25 subjects (20 males and 5 females) during four different sessions (resting with no intended head motion, head and facial motion, exercising on a cycle ergometer in a gym with no set restrictions, and talking in a real-world urban environment) together with reference pulse waveform signals recorded with a pulse oximeter at the sampling rate of 60 Hz. Gym recordings are five minutes long, whereas the length of other recordings is approximately one minute. When it comes to actual public availability of the data, only 24 recordings of six subjects are available. We used only the recordings covering resting (six recordings) and gym (six recordings) scenarios. By selecting the gym recordings, we covered a challenging scenario of uncontrolled motion in a real-world environment (uncontrolled lighting, presence of multiple subjects), which is not present in the other two data sets.  
PBDTrPPG consists of lossy compressed (H.264 codec) facial video recordings (recorded at 30 fps and 1080 \(\times\) 1920 pixels per frame) of three male subjects during three challenging scenarios (lighting variation in combination with different skin tones, motion scenarios, and resting after exercise, causing significant changes in PR) and reference ECG recordings (recorded at 1024 Hz). Only videos covering five different lighting conditions and three different skin tones (total of 15 recordings; two additional lighting scenarios with only one recording per each scenario were excluded) were included in our study from this data set. We excluded motion and resting after exercise scenarios because there are only three and one video(s) available, respectively. In addition, the type of motion scenarios is equivalent to that from the PURE data set, so inclusion of these recordings would not represent a major contribution to our study.  
With the selected data sets we included uncompressed and compressed videos, recordings made in controlled and uncontrolled environments and covering several different scenarios (rest, talking, different types of controlled and uncontrolled motion) and challenges (lighting variation and various skin tones).