Change BitBuf into uint64_t on all supported 64-bit platforms.
This means we need to flush the buffer less often, which is a
significant speed win. 32-bit platforms are unchanged.
Output bitstream is the same.
All API constraints are kept in place, e.g., you still cannot put_bits()
more than 31 bits at a time. This is so that codecs cannot accidentally
become 64-bit-only or similar.
Benchmarking on transcoding to various formats shows consistently
positive results:
dnxhd 25.60 fps -> 26.26 fps ( +2.6%)
dvvideo 24.88 fps -> 25.17 fps ( +1.2%)
ffv1 14.32 fps -> 14.58 fps ( +1.8%)
huffyuv 58.75 fps -> 63.27 fps ( +7.7%)
jpegls 6.22 fps -> 6.34 fps ( +1.8%)
magicyuv 57.10 fps -> 63.29 fps (+10.8%)
mjpeg 48.65 fps -> 49.01 fps ( +0.7%)
mpeg1video 76.41 fps -> 77.01 fps ( +0.8%)
mpeg2video 75.99 fps -> 77.43 fps ( +1.9%)
mpeg4 80.66 fps -> 81.37 fps ( +0.9%)
prores 12.35 fps -> 12.88 fps ( +4.3%)
prores_ks 16.20 fps -> 16.80 fps ( +3.7%)
rv20 62.80 fps -> 62.99 fps ( +0.3%)
utvideo 68.41 fps -> 76.32 fps (+11.6%)
Note that this includes video decoding and all other encoding work,
such as DCTs. If you isolate the actual bit-writing routines, it is
likely to be much more.
Benchmark details: Transcoding the first 30 seconds of Big Buck Bunny
in 1080p, Haswell 2.1 GHz, GCC 8.3, generally quantizer locked to
5.0. (Exceptions: DNxHD needs fixed bitrate, and JPEG-LS is so slow
that I only took the first 10 seconds, not 30.) All runs were done
ten times and single-threaded, top and bottom two results discarded to
get rid of outliers, arithmetic mean between the remaining six.
---
libavcodec/asvenc.c | 1 +
libavcodec/put_bits.h | 29 ++++++++++++++++++++++-------
2 files changed, 23 insertions(+), 7 deletions(-)
diff --git a/libavcodec/asvenc.c b/libavcodec/asvenc.c
index c2c940f365..28f7a94071 100644
--- a/libavcodec/asvenc.c
+++ b/libavcodec/asvenc.c
@@ -295,6 +295,7 @@ static int encode_frame(AVCodecContext *avctx, AVPacket
*pkt,
while (put_bits_count(&a->pb) & 31)
put_bits(&a->pb, 8, 0);
+ flush_put_bits(&a->pb);
size = put_bits_count(&a->pb) / 32;
if (avctx->codec_id == AV_CODEC_ID_ASV1) {
diff --git a/libavcodec/put_bits.h b/libavcodec/put_bits.h
index c6a8f3ac14..d8a5eb2810 100644
--- a/libavcodec/put_bits.h
+++ b/libavcodec/put_bits.h
@@ -32,9 +32,15 @@
#include "libavutil/intreadwrite.h"
#include "libavutil/avassert.h"
+#if ARCH_AARCH64 || ARCH_IA64 || ARCH_MIPS64 || ARCH_SPARC64 || ARCH_X86_64
+typedef uint64_t BitBuf;
+#define AV_WBBUF AV_WB64
+#define AV_WLBUF AV_WL64
+#else
typedef uint32_t BitBuf;
#define AV_WBBUF AV_WB32
#define AV_WLBUF AV_WL32
+#endif
static const int BUF_BITS = 8 * sizeof(BitBuf);
@@ -163,17 +169,11 @@ void avpriv_put_string(PutBitContext *pb, const char
*string,
void avpriv_copy_bits(PutBitContext *pb, const uint8_t *src, int length);
#endif
-/**
- * Write up to 31 bits into a bitstream.
- * Use put_bits32 to write 32 bits.
- */
-static inline void put_bits(PutBitContext *s, int n, BitBuf value)
+static inline void put_bits_no_assert(PutBitContext *s, int n, BitBuf value)
{
BitBuf bit_buf;
int bit_left;
- av_assert2(n <= 31 && value < (1UL << n));
-
bit_buf = s->bit_buf;
bit_left = s->bit_left;
@@ -215,6 +215,16 @@ static inline void put_bits(PutBitContext *s, int n,
BitBuf value)
s->bit_left = bit_left;
}
+/**
+ * Write up to 31 bits into a bitstream.
+ * Use put_bits32 to write 32 bits.
+ */
+static inline void put_bits(PutBitContext *s, int n, BitBuf value)
+{
+ av_assert2(n <= 31 && value < (1UL << n));
+ put_bits_no_assert(s, n, value);
+}
+
static inline void put_bits_le(PutBitContext *s, int n, BitBuf value)
{
BitBuf bit_buf;
@@ -258,6 +268,11 @@ static void av_unused put_bits32(PutBitContext *s,
uint32_t value)
BitBuf bit_buf;
int bit_left;
+ if (BUF_BITS > 32) {
+ put_bits_no_assert(s, 32, value);
+ return;
+ }
+
bit_buf = s->bit_buf;
bit_left = s->bit_left;
--
2.20.1
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