vc1: Split bits used in libavformat into a separate header

This reduces inter-library dependencies.

1 files changed, 92 insertions, 0 deletions

diff --git a/libavcodec/vc1_common.h b/libavcodec/vc1_common.h
new file mode 100644
index 0000000000..788d324cd8
--- /dev/null
+++ b/libavcodec/vc1_common.h
@@ -0,0 +1,92 @@
+/*
+ * VC-1 and WMV3 decoder
+ * Copyright (c) 2006-2007 Konstantin Shishkov
+ * Partly based on vc9.c (c) 2005 Anonymous, Alex Beregszaszi, Michael Niedermayer
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVCODEC_VC1_COMMON_H
+#define AVCODEC_VC1_COMMON_H
+
+#include <stdint.h>
+
+#include "libavutil/attributes.h"
+
+/** Markers used in VC-1 AP frame data */
+//@{
+enum VC1Code {
+    VC1_CODE_RES0       = 0x00000100,
+    VC1_CODE_ENDOFSEQ   = 0x0000010A,
+    VC1_CODE_SLICE,
+    VC1_CODE_FIELD,
+    VC1_CODE_FRAME,
+    VC1_CODE_ENTRYPOINT,
+    VC1_CODE_SEQHDR,
+};
+//@}
+
+#define IS_MARKER(x) (((x) & ~0xFF) == VC1_CODE_RES0)
+
+/** Available Profiles */
+//@{
+enum Profile {
+    PROFILE_SIMPLE,
+    PROFILE_MAIN,
+    PROFILE_COMPLEX, ///< TODO: WMV9 specific
+    PROFILE_ADVANCED
+};
+//@}
+
+/** Find VC-1 marker in buffer
+ * @return position where next marker starts or end of buffer if no marker found
+ */
+static av_always_inline const uint8_t* find_next_marker(const uint8_t *src, const uint8_t *end)
+{
+    uint32_t mrk = 0xFFFFFFFF;
+
+    if (end-src < 4)
+        return end;
+    while (src < end) {
+        mrk = (mrk << 8) | *src++;
+        if (IS_MARKER(mrk))
+            return src - 4;
+    }
+    return end;
+}
+
+static av_always_inline int vc1_unescape_buffer(const uint8_t *src, int size, uint8_t *dst)
+{
+    int dsize = 0, i;
+
+    if (size < 4) {
+        for (dsize = 0; dsize < size; dsize++)
+            *dst++ = *src++;
+        return size;
+    }
+    for (i = 0; i < size; i++, src++) {
+        if (src[0] == 3 && i >= 2 && !src[-1] && !src[-2] && i < size-1 && src[1] < 4) {
+            dst[dsize++] = src[1];
+            src++;
+            i++;
+        } else
+            dst[dsize++] = *src;
+    }
+    return dsize;
+}
+
+#endif /* AVCODEC_VC1_COMMON_H */