We start by asking an interesting yet challenging question, "If an eyewitness
can only recall the eye features of the suspect, such that the forensic artist
can only produce a sketch of the eyes (e.g., the top-left sketch shown in Fig.
1), can advanced computer vision techniques help generate the whole face
image?" A more generalized question is that if a large proportion (e.g., more
than 50%) of the face/sketch is missing, can a realistic whole face
sketch/image still be estimated. Existing face completion and generation
methods either do not conduct domain transfer learning or can not handle large
missing area. For example, the inpainting approach tends to blur the generated
region when the missing area is large (i.e., more than 50%). In this paper, we
exploit the potential of deep learning networks in filling large missing region
(e.g., as high as 95% missing) and generating realistic faces with
high-fidelity in cross domains. We propose the recursive generation by
bidirectional transformation networks (r-BTN) that recursively generates a
whole face/sketch from a small sketch/face patch. The large missing area and
the cross domain challenge make it difficult to generate satisfactory results
using a unidirectional cross-domain learning structure. On the other hand, a
forward and backward bidirectional learning between the face and sketch domains
would enable recursive estimation of the missing region in an incremental
manner (Fig. 1) and yield appealing results. r-BTN also adopts an adversarial
constraint to encourage the generation of realistic faces/sketches. Extensive
experiments have been conducted to demonstrate the superior performance from
r-BTN as compared to existing potential solutions.

使用递归生成双向转换网络 (r-BTN) 进行大面积缺失填补，生成逼真的人脸 / 素描，并对比现有潜力解决方案进行了广泛的实验来证明其优越性。