X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fgolomb.h;h=4d531cf8053c598a41480bc9445c336fcd62694c;hb=1ab74bc19354aedfb9afe71515952254753a75cc;hp=efb1eff8aa49a22fdfec90c532bdf1a5ef80e362;hpb=b065c71e9d2ad3c5d65f924a4003e3a7ee595417;p=ffmpeg

diff --git a/libavcodec/golomb.h b/libavcodec/golomb.h
index efb1eff8aa4..4d531cf8053 100644
--- a/libavcodec/golomb.h
+++ b/libavcodec/golomb.h
@@ -49,11 +49,33 @@ 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)
 {
     unsigned int buf;
 
+#if CACHED_BITSTREAM_READER
+    buf = show_bits_long(gb, 32);
+
+    if (buf >= (1 << 27)) {
+        buf >>= 32 - 9;
+        skip_bits_long(gb, ff_golomb_vlc_len[buf]);
+
+        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--;
+
+        return buf;
+    }
+#else
     OPEN_READER(re, gb);
     UPDATE_CACHE(re, gb);
     buf = GET_CACHE(re, gb);
@@ -68,15 +90,14 @@ 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--;
 
         return buf;
     }
+#endif
 }
 
 /**
@@ -95,12 +116,20 @@ 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)
 {
     unsigned int buf;
 
+#if CACHED_BITSTREAM_READER
+    buf = show_bits_long(gb, 32);
+
+    buf >>= 32 - 9;
+    skip_bits_long(gb, ff_golomb_vlc_len[buf]);
+#else
+
     OPEN_READER(re, gb);
     UPDATE_CACHE(re, gb);
     buf = GET_CACHE(re, gb);
@@ -108,6 +137,7 @@ static inline int get_ue_golomb_31(GetBitContext *gb)
     buf >>= 32 - 9;
     LAST_SKIP_BITS(re, gb, ff_golomb_vlc_len[buf]);
     CLOSE_READER(re, gb);
+#endif
 
     return ff_ue_golomb_vlc_code[buf];
 }
@@ -116,6 +146,33 @@ static inline unsigned get_interleaved_ue_golomb(GetBitContext *gb)
 {
     uint32_t buf;
 
+#if CACHED_BITSTREAM_READER
+    buf = show_bits_long(gb, 32);
+
+    if (buf & 0xAA800000) {
+        buf >>= 32 - 8;
+        skip_bits_long(gb, ff_interleaved_golomb_vlc_len[buf]);
+
+        return ff_interleaved_ue_golomb_vlc_code[buf];
+    } else {
+        unsigned ret = 1;
+
+        do {
+            buf >>= 32 - 8;
+            skip_bits_long(gb, FFMIN(ff_interleaved_golomb_vlc_len[buf], 8));
+
+            if (ff_interleaved_golomb_vlc_len[buf] != 9) {
+                ret <<= (ff_interleaved_golomb_vlc_len[buf] - 1) >> 1;
+                ret  |= ff_interleaved_dirac_golomb_vlc_code[buf];
+                break;
+            }
+            ret = (ret << 4) | ff_interleaved_dirac_golomb_vlc_code[buf];
+            buf = show_bits_long(gb, 32);
+        } while (get_bits_left(gb) > 0);
+
+        return ret - 1;
+    }
+#else
     OPEN_READER(re, gb);
     UPDATE_CACHE(re, gb);
     buf = GET_CACHE(re, gb);
@@ -147,6 +204,7 @@ static inline unsigned get_interleaved_ue_golomb(GetBitContext *gb)
         CLOSE_READER(re, gb);
         return ret - 1;
     }
+#endif
 }
 
 /**
@@ -184,6 +242,28 @@ static inline int get_se_golomb(GetBitContext *gb)
 {
     unsigned int buf;
 
+#if CACHED_BITSTREAM_READER
+    buf = show_bits_long(gb, 32);
+
+    if (buf >= (1 << 27)) {
+        buf >>= 32 - 9;
+        skip_bits_long(gb, ff_golomb_vlc_len[buf]);
+
+        return ff_se_golomb_vlc_code[buf];
+    } else {
+        int log = 2 * av_log2(buf) - 31;
+        buf >>= log;
+
+        skip_bits_long(gb, 32 - log);
+
+        if (buf & 1)
+            buf = -(buf >> 1);
+        else
+            buf = (buf >> 1);
+
+        return buf;
+    }
+#else
     OPEN_READER(re, gb);
     UPDATE_CACHE(re, gb);
     buf = GET_CACHE(re, gb);
@@ -210,6 +290,7 @@ static inline int get_se_golomb(GetBitContext *gb)
 
         return buf;
     }
+#endif
 }
 
 static inline int get_se_golomb_long(GetBitContext *gb)
@@ -223,6 +304,30 @@ static inline int get_interleaved_se_golomb(GetBitContext *gb)
 {
     unsigned int buf;
 
+#if CACHED_BITSTREAM_READER
+    buf = show_bits_long(gb, 32);
+
+    if (buf & 0xAA800000) {
+        buf >>= 32 - 8;
+        skip_bits_long(gb, ff_interleaved_golomb_vlc_len[buf]);
+
+        return ff_interleaved_se_golomb_vlc_code[buf];
+    } else {
+        int log;
+        skip_bits(gb, 8);
+        buf |= 1 | show_bits(gb, 24);
+
+        if ((buf & 0xAAAAAAAA) == 0)
+            return INVALID_VLC;
+
+        for (log = 31; (buf & 0x80000000) == 0; log--)
+            buf = (buf << 2) - ((buf << log) >> (log - 1)) + (buf >> 30);
+
+        skip_bits_long(gb, 63 - 2 * log - 8);
+
+        return (signed) (((((buf << log) >> log) - 1) ^ -(buf & 0x1)) + 1) >> 1;
+    }
+#else
     OPEN_READER(re, gb);
     UPDATE_CACHE(re, gb);
     buf = GET_CACHE(re, gb);
@@ -250,6 +355,7 @@ static inline int get_interleaved_se_golomb(GetBitContext *gb)
 
         return (signed) (((((buf << log) >> log) - 1) ^ -(buf & 0x1)) + 1) >> 1;
     }
+#endif
 }
 
 static inline int dirac_get_se_golomb(GetBitContext *gb)
@@ -273,6 +379,24 @@ static inline int get_ur_golomb(GetBitContext *gb, int k, int limit,
     unsigned int buf;
     int log;
 
+#if CACHED_BITSTREAM_READER
+    buf = show_bits_long(gb, 32);
+
+    log = av_log2(buf);
+
+    if (log > 31 - limit) {
+        buf >>= log - k;
+        buf  += (30 - log) << k;
+        skip_bits_long(gb, 32 + k - log);
+
+        return buf;
+    } else {
+        skip_bits_long(gb, limit);
+        buf = get_bits_long(gb, esc_len);
+
+        return buf + limit - 1;
+    }
+#else
     OPEN_READER(re, gb);
     UPDATE_CACHE(re, gb);
     buf = GET_CACHE(re, gb);
@@ -297,6 +421,7 @@ static inline int get_ur_golomb(GetBitContext *gb, int k, int limit,
 
         return buf + limit - 1;
     }
+#endif
 }
 
 /**
@@ -308,6 +433,35 @@ static inline int get_ur_golomb_jpegls(GetBitContext *gb, int k, int limit,
     unsigned int buf;
     int log;
 
+#if CACHED_BITSTREAM_READER
+    buf = show_bits_long(gb, 32);
+
+    log = av_log2(buf);
+
+    if (log - k >= 1 && 32 - log < limit) {
+        buf >>= log - k;
+        buf  += (30 - log) << k;
+        skip_bits_long(gb, 32 + k - log);
+
+        return buf;
+    } else {
+        int i;
+        for (i = 0;
+             i < limit && get_bits1(gb) == 0 && get_bits_left(gb) > 0;
+             i++);
+
+        if (i < limit - 1) {
+            buf = get_bits_long(gb, k);
+
+            return buf + (i << k);
+        } else if (i == limit - 1) {
+            buf = get_bits_long(gb, esc_len);
+
+            return buf + 1;
+        } else
+            return -1;
+    }
+#else
     OPEN_READER(re, gb);
     UPDATE_CACHE(re, gb);
     buf = GET_CACHE(re, gb);
@@ -326,15 +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) {
@@ -364,6 +522,7 @@ static inline int get_ur_golomb_jpegls(GetBitContext *gb, int k, int limit,
         CLOSE_READER(re, gb);
         return buf;
     }
+#endif
 }
 
 /**