R BioStyle渐晕图-无效参数"；-/图html"；

当我试图编译包含RStudio图形的

BiocStyle

vignette时，会收到奇怪的警告消息。我相信这与自动剪辑图像有关，但我还没有完全弄清楚到底是怎么回事

最低工作示例：

---
title: "Untitled"
author: "test"
output: 
    BiocStyle::html_document
vignette: >
  %\VignetteIndexEntry{Vignette Title}
  %\VignetteEngine{knitr::rmarkdown}
  %\VignetteEncoding{UTF-8}  
---

```{r pressure, echo=FALSE}
plot(pressure)
```

在将.rmd编译为.md时引发警告：

无效参数-/figure html

但它会进一步编译为.html，但会发出额外警告：

output file: rmd_test.knit.md


Output created: rmd_test.html
Warning messages:
1: running command 'C:\WINDOWS\system32\cmd.exe /c convert "rmd_test_files/figure-html/pressure-1.png" -trim "rmd_test_files/figure-html/pressure-1.png"' had status 4 
2: In shell(paste(c(cmd, args), collapse = " ")) :
  'convert "rmd_test_files/figure-html/pressure-1.png" -trim "rmd_test_files/figure-html/pressure-1.png"' execution failed with error code 4

我运行的是Windows10和最新的R3.4.3

sessionInfo()

## R version 3.4.3 (2017-11-30)
## Platform: x86_64-w64-mingw32/x64 (64-bit)
## Running under: Windows 10 x64 (build 16299)
## 
## Matrix products: default
## 
## locale:
## [1] LC_COLLATE=English_United Kingdom.1252 
## [2] LC_CTYPE=English_United Kingdom.1252   
## [3] LC_MONETARY=English_United Kingdom.1252
## [4] LC_NUMERIC=C                           
## [5] LC_TIME=English_United Kingdom.1252    
## 
## attached base packages:
## [1] stats     graphics  grDevices utils     datasets  methods   base     
## 
## other attached packages:
## [1] BiocStyle_2.6.1
## 
## loaded via a namespace (and not attached):
##  [1] compiler_3.4.3  backports_1.1.2 bookdown_0.6    magrittr_1.5   
##  [5] rprojroot_1.3-2 tools_3.4.3     htmltools_0.3.6 yaml_2.1.16    
##  [9] Rcpp_0.12.15    stringi_1.1.6   rmarkdown_1.8   knitr_1.19     
## [13] xfun_0.1        stringr_1.2.0   digest_0.6.15   evaluate_0.10.1

---

我也面临同样的问题。如果你找到了一个解决方案，如果你能把它贴在这里就太好了。谢谢