In this paper we introduce AFFDEX 2.0 – a toolkit for analyzing facial expressions in the wild, that is, it is intended for users aiming to; a) estimate the 3D head pose, b) detect facial Action Units (AUs), c) recognize basic emotions and 2 new emotional states (sentimentality and confusion), and d) detect high-level expressive metrics like blink and attention. AFFDEX 2.0 models are mainly based on Deep Learning, and are trained using a large-scale naturalistic dataset consisting of thousands of participants from different demographic groups. AFFDEX 2.0 is an enhanced version of our previous toolkit [36], that is capable of tracking faces at challenging conditions, detecting more accurately facial expressions, and recognizing new emotional states (sentimentality and confusion). AFFDEX 2.0 outperforms the state-of-the-art methods in AU detection and emotion recognition. AFFDEX 2.0 can process multiple faces in real time, and is working across the Windows and Linux platforms.
Models that can learn orthogonal representations for different facial attributes (e.g. pose, lighting, identity, expressions) have proven to be beneficial for both discriminative and generative tasks. In this work, we propose the universal facial encoder (UFE) that can simultaneously encode different facial attributes as disentangled features from a single face image. We propose a variety of qualitative and quantitative metrics to evaluate feature orthogonality of the UFE and demonstrate superior disentanglement compared to traditional single-attribute encoding. We also show that these features can then be used to train lightweight prediction heads for multiple downstream classification tasks. Moreover, coupling the UFE with a style-based decoder enables hallucination of new face images composed of attributes taken from different samples. As experimentally demonstrated, the UFE allows us to pick and choose these attributes from label-disjoint datasets. A catalog of such synthetic composites can be used as supplemental training data or simply as stock photos.
Emotion recognition has received considerable attention from the Computer Vision community in the last 20 years. However, most of the research focused on analyzing the six basic emotions (e.g. joy, anger, surprise), with a limited work directed to other affective states. In this paper, we tackle sentimentality (strong feeling of heartwarming or nostalgia), a new emotional state that has few works in the literature, and no guideline defining its facial markers. To this end, we first collect a dataset of 4.9K videos of participants watching some sentimental and non-sentimental ads, and then we label the moments evoking sentimentality in the ads. Second, we use the ad-level labels and the facial Action Units (AUs) activation across different frames for defining some weak frame-level sentimentality labels. Third, we train a Multilayer Perceptron (MLP) using the AUs activation for sentimentality detection. Finally, we define two new ad-level metrics for evaluating our model performance. Quantitative and qualitative results show promising results for sentimentality detection. To the best of our knowledge this is the first work to address the problem of sentimentality detection.
Distracted drivers are dangerous drivers. Equipping advanced driver assistance systems (ADAS) with the ability to detect driver distraction can help prevent accidents and improve driver safety. In order to detect driver distraction, an ADAS must be able to monitor their visual attention. We propose a model that takes as input a patch of the driver's face along with a crop of the eye-region and classifies their glance into 6 coarse regions-of-interest (ROIs) in the vehicle. We demonstrate that an hourglass network, trained with an additional reconstruction loss, allows the model to learn stronger contextual feature representations than a traditional encoder-only classification module. To make the system robust to subject-specific variations in appearance and behavior, we design a personalized hourglass model tuned with an auxiliary input representing the driver's baseline glance behavior. Finally, we present a weakly supervised multi-domain training regimen that enables the hourglass to jointly learn representations from different domains (varying in camera type, angle), utilizing unlabeled samples and thereby reducing annotation cost.
We present a real-time facial expression recognition toolkit that can automatically code the expressions of multiple people simultaneously. The toolkit is available across major mobile and desktop platforms (Android, iOS, Windows). The system is trained on the world's largest dataset of facial expressions and has been optimized to operate on mobile devices and with very few false detections. The toolkit offers the potential for the design of novel interfaces that respond to users' emotional states based on their facial expressions. We present a demonstration application that provides real-time visualization of the expressions captured by the camera.
A supervised machine learning approach to remote video-based heart rate (HR) estimation is proposed. We demonstrate the possibility of training a discriminative statistical model to estimate the Blood Volume Pulse signal (BVP) from the human face using ambient light and any off-the-shelf webcam. The proposed algorithm is 120 times faster than state of the art approach and returns a confidence metric to evaluate the HR estimates plausibility. The algorithm was evaluated against the state-of-the-art on 120 minutes of face videos, the largest video-based heart rate evaluation to date. The evaluation results showed a 53% decrease in the Root Mean Squared Error (RMSE) compared to state-of-the-art.
Asymmetric facial expressions, such as a smirk, are strong emotional signals indicating valence as well as discrete emotion states such as contempt, doubt and defiance. Yet, the automated detection of asymmetric facial action units has been largely ignored to date. We present the first automated system for detecting spontaneous asymmetric lip movements as people watched online video commercials. Many of these expressions were subtle, fleeting and co-occurred with head movements. For each frame of the video, the face is located, cropped, scaled and flipped around the vertical axis. Both the normalized and flipped versions of the face feed a right hemiface trained (RHT) classifier. The difference between both outputs indicates the presence of asymmetric facial actions on a frame-basis. The system was tested on over 500 facial videos that were crowdsourced over the Internet, with an overall 2AFC score of 88.2% on spontaneous videos. A dynamic model based on template matching is then used to identify asymmetric events that have a clear onset and offset. The event detector reduced the false alarm rate due to tracking inaccuracies, head movement, eating and non-uniform lighting. For an event that happens once every 20 videos, we are able to detect half of the occurrences with a false alarm rate of 1 event every 85 videos. We demonstrate the application of this work to measuring viewer affective responses to video content.