【报Bug】canvas canvasToTempFilePath的quality参数无效 0-1之前设置参数 图片大小完全没有变化

示例代码：

实际案例可以参考插件市场的 https://ext.dcloud.net.cn/plugin?id=2316

压缩代码

<template>  
  <view class="compress">  
    <canvas  
      canvas-id="compress-canvas"  
      :style="{ width: canvasSize.width, height: canvasSize.height }"  
    ></canvas>  
  </view>  
</template>  

<script>  
export default {  
  data() {  
    return {  
      pic: "",  
      canvasSize: {  
        width: 0,  
        height: 0,  
      },  
    };  
  },  
  methods: {  
    // 压缩  
    compressFun(params) {  
      let that = this;  
      return new Promise((resolve, reject) => {  
        // 等待图片信息  
        that  
          .getImageInfo(params.src)  
          .then((info) => {  
            if (!info) {  
              reject("获取图片信息异常");  
              return;  
            }  

            // 设置最大 & 最小 尺寸  
            const maxSize = params.maxSize || 1080;  
            const minSize = params.minSize || 640;  

            // 当前图片尺寸  
            let { width, height } = info;  

            // 非 H5 平台进行最小尺寸校验  
            // #ifndef H5  
            if (width <= minSize && height <= minSize) {  
              resolve(params.src);  
              return;  
            }  
            // #endif  

            // 最大尺寸计算  
            if (width > maxSize || height > maxSize) {  
              if (width > height) {  
                height = Math.floor(height / (width / maxSize));  
                width = maxSize;  
              } else {  
                width = Math.floor(width / (height / maxSize));  
                height = maxSize;  
              }  
            }  

            // 设置画布尺寸  
            that.$set(that, "canvasSize", {  
              width: `${width}px`,  
              height: `${height}px`,  
            });  

            // Vue.nextTick 回调在 App 有异常，则使用 setTimeout 等待DOM更新  
            setTimeout(() => {  
              const ctx = uni.createCanvasContext("compress-canvas", that);  
              ctx.clearRect(0, 0, width, height);  
              ctx.drawImage(info.path, 0, 0, width, height);  
              try {  
                ctx.draw(false, () => {  
                  uni.canvasToTempFilePath(  
                    {  
                      x: 0,  
                      y: 0,  
                      width: width,  
                      height: height,  
                      destWidth: width,  
                      destHeight: height,  
                      canvasId: "compress-canvas",  
                      fileType: params.fileType || "png",  
                      quality: params.quality || 0.9,  
                      success: (res) => {  
                        debugger;  
                        // 在H5平台下，tempFilePath 为 base64  
                        resolve(res.tempFilePath);  
                      },  
                      fail: (err) => {  
                        reject(null);  
                      },  
                    },  
                    this  
                  );  
                });  
              } catch (error) {  
                console.error(error);  
              }  
            }, 300);  
          })  
          .catch(() => {  
            reject("获取图片信息异常");  
          });  
      });  
    },  
    // 获取图片信息  
    getImageInfo(src) {  
      return new Promise((resolve, reject) => {  
        uni.getImageInfo({  
          src,  
          success: (info) => {  
            resolve(info);  
          },  
          fail: () => {  
            reject(null);  
          },  
        });  
      });  
    },  
    // 批量压缩  
    compress(params) {  
      debugger;  
      // index:进度，done:成功，fail:失败  
      let [index, done, fail] = [0, 0, 0];  
      // 压缩完成的路径集合  
      let paths = [];  
      // 待压缩的图片  
      let waitList = [];  
      if (typeof params.src == "string") {  
        waitList = [params.src];  
      } else {  
        waitList = params.src;  
      }  
      // 批量压缩方法  
      let batch = () => {  
        return new Promise((resolve) => {  
          // 开始  
          let start = async () => {  
            params.progress &&  
              params.progress({  
                done,  
                fail,  
                count: waitList.length,  
              });  
            // 等待图片压缩方法返回  
            let path = await next();  
            if (path) {  
              done++;  
              paths.push(path);  
            } else {  
              fail++;  
            }  

            index++;  
            // 压缩完成  
            if (index >= waitList.length) {  
              resolve(true);  
            } else {  
              start();  
            }  
          };  
          start();  
        });  
      };  
      // 依次调用压缩方法  
      let next = () => {  
        return this.compressFun({  
          src: waitList[index],  
          maxSize: params.maxSize,  
          fileType: params.fileType,  
          quality: params.quality,  
          minSize: params.minSize,  
        });  
      };  

      // 全部压缩完成后调用  
      return new Promise((resolve, reject) => {  
        // 批量压缩方法回调  
        batch()  
          .then((res) => {  
            if (res) {  
              if (typeof params.src == "string") {  
                resolve(paths[0]);  
              } else {  
                resolve(paths);  
              }  
            }  
          })  
          .catch(() => {  
            reject(null);  
          });  
      });  
    },  
  },  
};  
</script>  

<style lang="scss" scoped>  
.compress {  
  position: fixed;  
  width: 12px;  
  height: 12px;  
  overflow: hidden;  
  top: -99999px;  
  left: 0;  
}  
</style>

操作步骤：

调整 quality 值即可

预期结果：

根据 quality 的不同 更改图片的大小 实现图片压缩效果

实际结果：

quality 改变后 图片大小没有任何变化 经过测试不管是CLI还是HB 运行 不管是 APP 和 H5 都一样没有变化
H5特别容易看 因为返回的base64 length就看出来了