lavc: add a HEVC decoder.

Initially written by Guillaume Martres <smarter@ubuntu.com> as a GSoC
project. Further contributions by the OpenHEVC project and other
developers, namely:

Mickaël Raulet <mraulet@insa-rennes.fr>
Seppo Tomperi <seppo.tomperi@vtt.fi>
Gildas Cocherel <gildas.cocherel@laposte.net>
Khaled Jerbi <khaled_jerbi@yahoo.fr>
Wassim Hamidouche <wassim.hamidouche@insa-rennes.fr>
Vittorio Giovara <vittorio.giovara@gmail.com>
Jan Ekström <jeebjp@gmail.com>
Anton Khirnov <anton@khirnov.net>
Martin Storsjö <martin@martin.st>
Luca Barbato <lu_zero@gentoo.org>
Yusuke Nakamura <muken.the.vfrmaniac@gmail.com>

Signed-off-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

1 files changed, 20 insertions, 0 deletions

diff --git a/libavcodec/cabac_functions.h b/libavcodec/cabac_functions.h
index 8a7275d9de..b84258bfa7 100644
--- a/libavcodec/cabac_functions.h
+++ b/libavcodec/cabac_functions.h
@@ -160,4 +160,24 @@ static int av_unused get_cabac_terminate(CABACContext *c){
     }
 }
 
+/**
+ * Skip @p n bytes and reset the decoder.
+ * @return the address of the first skipped byte or NULL if there's less than @p n bytes left
+ */
+static av_unused const uint8_t* skip_bytes(CABACContext *c, int n) {
+    const uint8_t *ptr = c->bytestream;
+
+    if (c->low & 0x1)
+        ptr--;
+#if CABAC_BITS == 16
+    if (c->low & 0x1FF)
+        ptr--;
+#endif
+    if ((int) (c->bytestream_end - ptr) < n)
+        return NULL;
+    ff_init_cabac_decoder(c, ptr + n, c->bytestream_end - ptr - n);
+
+    return ptr;
+}
+
 #endif /* AVCODEC_CABAC_FUNCTIONS_H */