libv4lconvert: Fix se401 decompression

Somehow I've managed to commit a non working version.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>

diff --git a/lib/libv4lconvert/se401.c b/lib/libv4lconvert/se401.c
index ccfcda0..b38ef38 100644 (file)
--- a/lib/libv4lconvert/se401.c
+++ b/lib/libv4lconvert/se401.c
@@ -46,9 +46,9 @@ static void wr_pixel(int p, uint8_t **dest, int pitch, int *x)
 }
 
 enum decode_state {
-        get_len,
-        sign_bit,
-        other_bits,
+       get_len,
+       sign_bit,
+       other_bits,
 };
 
 static int decode_JangGu(const uint8_t *data, int bits, int plen, int pixels,
@@ -79,17 +79,20 @@ static int decode_JangGu(const uint8_t *data, int bits, int plen, int pixels,
                                        }
                                }
                                break;
-                        case sign_bit:
-                               if (!bit)
+                       case sign_bit:
+                               if (bit)
+                                       value = 0;
+                               else
                                        value = -(1 << len) + 1;
-                                /* fall through for positive number and
-                                   len == 1 handling */
-                        case other_bits:
+                               state = other_bits;
+                               /* fall through for positive number and
+                                  len == 1 handling */
+                       case other_bits:
                                len--;
                                value += bit << len;
                                if (len == 0) {
-                                       /* Done write pixel and get bit len of
-                                          the next one */
+                                       /* Done write pixel and get bit len of
+                                          the next one */
                                        state = get_len;
                                        wr_pixel(value, dest, pitch, x);
                                        if (!--pixels)