change default quality from 80 to 95 for bigger and deeper network (#…

…4164)

example/image-classification/README.md

@@ -72,11 +72,11 @@ python tools/im2rec.py --list True --recursive True --train-ratio 0.95 mydata im
 ```
 
 Then we generate the `.rec` files. We resize the images such that the short edge
-is at least 480px and save them with 90/100 quality. We also use 16 threads to
+is at least 480px and save them with 95/100 quality. We also use 16 threads to
 accelerate the packing.
 
 ```bash
-python tools/im2rec.py --resize 480 --quality 90 --num-thread 16 mydata img_data
+python tools/im2rec.py --resize 480 --quality 95 --num-thread 16 mydata img_data
 ```
 
 Hints:

example/image-classification/data/caltech256.sh

@@ -36,8 +36,8 @@ mv caltech256-val_train.lst caltech256-val.lst
 rm caltech256-val_*
 
 # generate rec files
-python ${MX_DIR}/tools/im2rec.py --resize 256 --quality 90 --num-thread 16 caltech256-val 256_ObjectCategories/
-python ${MX_DIR}/tools/im2rec.py --resize 256 --quality 90 --num-thread 16 caltech256-train ${TRAIN_DIR}/
+python ${MX_DIR}/tools/im2rec.py --resize 256 --quality 95 --num-thread 16 caltech256-val 256_ObjectCategories/
+python ${MX_DIR}/tools/im2rec.py --resize 256 --quality 95 --num-thread 16 caltech256-train ${TRAIN_DIR}/
 
 # clean
 rm -rf ${TRAIN_DIR} 256_ObjectCategories/

python/mxnet/recordio.py

@@ -241,7 +241,7 @@ def unpack_img(s, iscolor=-1):
     img = cv2.imdecode(img, iscolor)
     return header, img
 
-def pack_img(header, img, quality=80, img_fmt='.jpg'):
+def pack_img(header, img, quality=95, img_fmt='.jpg'):
     """pack an image into MXImageRecord
 
     Parameters

tools/im2rec.cc

@@ -53,7 +53,7 @@ int main(int argc, char *argv[]) {
            "\tnsplit=NSPLIT[default=1] used for part generation, logically split the image.list to NSPLIT parts by position\n"\
            "\tpart=PART[default=0] used for part generation, pack the images from the specific part in image.list\n"\
            "\tcenter_crop=CENTER_CROP[default=0] specify whether to crop the center image to make it square.\n"\
-           "\tquality=QUALITY[default=80] JPEG quality for encoding (1-100, default: 80) or PNG compression for encoding (1-9, default: 3).\n"\
+           "\tquality=QUALITY[default=95] JPEG quality for encoding (1-100, default: 95) or PNG compression for encoding (1-9, default: 3).\n"\
            "\tencoding=ENCODING[default='.jpg'] Encoding type. Can be '.jpg' or '.png'\n"\
            "\tinter_method=INTER_METHOD[default=1] NN(0) BILINEAR(1) CUBIC(2) AREA(3) LANCZOS4(4) AUTO(9) RAND(10).\n"\
            "\tunchanged=UNCHANGED[default=0] Keep the original image encoding, size and color. If set to 1, it will ignore the others parameters.\n");
@@ -65,21 +65,21 @@ int main(int argc, char *argv[]) {
   int nsplit = 1;
   int partid = 0;
   int center_crop = 0;
-  int quality = 80;
+  int quality = 95;
   int color_mode = CV_LOAD_IMAGE_COLOR;
   int unchanged = 0;
   int inter_method = CV_INTER_LINEAR;
   std::string encoding(".jpg");
   for (int i = 4; i < argc; ++i) {
     char key[128], val[128];
     int effct_len = 0;
-    
+
 #ifdef _MSC_VER
     effct_len = sscanf_s(argv[i], "%[^=]=%s", key, sizeof(key), val, sizeof(val));
 #else
     effct_len = sscanf(argv[i], "%[^=]=%s", key, val);
 #endif
-    
+
     if (effct_len == 2) {
       if (!strcmp(key, "resize")) new_size = atoi(val);
       if (!strcmp(key, "label_width")) label_width = atoi(val);

tools/im2rec.py

@@ -179,7 +179,7 @@ def parse_args():
         be packed by default.')
     rgroup.add_argument('--center-crop', type=bool, default=False,
                         help='specify whether to crop the center image to make it rectangular.')
-    rgroup.add_argument('--quality', type=int, default=80,
+    rgroup.add_argument('--quality', type=int, default=95,
                         help='JPEG quality for encoding, 1-100; or PNG compression for encoding, 1-9')
     rgroup.add_argument('--num-thread', type=int, default=1,
                         help='number of thread to use for encoding. order of images will be different\
@@ -195,7 +195,7 @@ def parse_args():
     rgroup.add_argument('--shuffle', default=True, help='If this is set as True, \
         im2rec will randomize the image order in <prefix>.lst')
     rgroup.add_argument('--pack-label', default=False,
-        help='Whether to also pack multi dimensional label in the record file') 
+        help='Whether to also pack multi dimensional label in the record file')
     args = parser.parse_args()
     args.prefix = os.path.abspath(args.prefix)
     args.root = os.path.abspath(args.root)