X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fgolomb.h;h=4d531cf8053c598a41480bc9445c336fcd62694c;hb=b9fff6e15e73dc995695db9be8db084238cca14c;hp=5c25883626356ebe90018ca98274ebb7ab934073;hpb=022fa7a24ea8f5000e7b6a50e57cc752f417da47;p=ffmpeg

diff --git a/libavcodec/golomb.h b/libavcodec/golomb.h
index 5c258836263..4d531cf8053 100644
--- a/libavcodec/golomb.h
+++ b/libavcodec/golomb.h
@@ -49,6 +49,8 @@ extern const uint8_t ff_interleaved_dirac_golomb_vlc_code[256];
 
 /**
  * Read an unsigned Exp-Golomb code in the range 0 to 8190.
+ *
+ * @returns the read value or a negative error code.
  */
 static inline int get_ue_golomb(GetBitContext *gb)
 {
@@ -64,9 +66,12 @@ static inline int get_ue_golomb(GetBitContext *gb)
         return ff_ue_golomb_vlc_code[buf];
     } else {
         int log = 2 * av_log2(buf) - 31;
+
+        skip_bits_long(gb, 32 - log);
+        if (log < 7)
+            return AVERROR_INVALIDDATA;
         buf >>= log;
         buf--;
-        skip_bits_long(gb, 32 - log);
 
         return buf;
     }
@@ -85,10 +90,8 @@ static inline int get_ue_golomb(GetBitContext *gb)
         int log = 2 * av_log2(buf) - 31;
         LAST_SKIP_BITS(re, gb, 32 - log);
         CLOSE_READER(re, gb);
-        if (log < 7) {
-            av_log(NULL, AV_LOG_ERROR, "Invalid UE golomb code\n");
+        if (log < 7)
             return AVERROR_INVALIDDATA;
-        }
         buf >>= log;
         buf--;
 
@@ -113,7 +116,8 @@ static inline unsigned get_ue_golomb_long(GetBitContext *gb)
 
 /**
  * read unsigned exp golomb code, constraint to a max of 31.
- * the return value is undefined if the stored value exceeds 31.
+ * If the value encountered is not in 0..31, the return value
+ * is outside the range 0..30.
  */
 static inline int get_ue_golomb_31(GetBitContext *gb)
 {
@@ -311,7 +315,7 @@ static inline int get_interleaved_se_golomb(GetBitContext *gb)
     } else {
         int log;
         skip_bits(gb, 8);
-        buf |= 1 | show_bits_long(gb, 24);
+        buf |= 1 | show_bits(gb, 24);
 
         if ((buf & 0xAAAAAAAA) == 0)
             return INVALID_VLC;
@@ -476,15 +480,19 @@ static inline int get_ur_golomb_jpegls(GetBitContext *gb, int k, int limit,
         return buf;
     } else {
         int i;
-        for (i = 0; i < limit && SHOW_UBITS(re, gb, 1) == 0; i++) {
+        for (i = 0; i + MIN_CACHE_BITS <= limit && SHOW_UBITS(re, gb, MIN_CACHE_BITS) == 0; i += MIN_CACHE_BITS) {
             if (gb->size_in_bits <= re_index) {
                 CLOSE_READER(re, gb);
                 return -1;
             }
-            LAST_SKIP_BITS(re, gb, 1);
+            LAST_SKIP_BITS(re, gb, MIN_CACHE_BITS);
             UPDATE_CACHE(re, gb);
         }
-        SKIP_BITS(re, gb, 1);
+        for (; i < limit && SHOW_UBITS(re, gb, 1) == 0; i++) {
+            SKIP_BITS(re, gb, 1);
+        }
+        LAST_SKIP_BITS(re, gb, 1);
+        UPDATE_CACHE(re, gb);
 
         if (i < limit - 1) {
             if (k) {