turbo jpeg 解码缩小图片出错

Question

turbo jpeg 解码图片，缩小到原图的1/64时出错，提示：
tjDecompress2(): Could not scale down to desired image dimensions
什么原因？原图大小为3264*2448

int image_width, image_height, subsample;
int result = tjDecompressHeader2(handle, jpeg_buffer, jpeg_size,
        &image_width, &image_height, &subsample);
LOG_D("image_width %d , image_height %d , subsample %d ", image_width, image_height, subsample);
int scale = sampleSize;
tjscalingfactor sf;
sf.num = 1;
sf.denom = sampleSize;
image_width = TJSCALED(image_width, sf);
image_height = TJSCALED(image_height, sf);
LOG_D("after scale, image_width %d , image_height %d", image_width, image_height);
int stride = image_width * 4;
unsigned char*  out_buffer = (unsigned char*)malloc(stride * image_height);
int flags = 0;
flags |= 0;
int pixelfmt = TJPF_RGBA;
bool decompress = tjDecompress2(handle, jpeg_buffer, jpeg_size, out_buffer, image_width, 0,
        image_height, pixelfmt, flags);
if (decompress) {
    LOG_E("decompress fail %s\n", tjGetErrorStr());
}
tjDestroy(handle);