Add an entropy setting to choose between CAVLC and CABAC.
Signed-off-by: Rick Kern <ker...@gmail.com>
---
libavcodec/videotoolboxenc.c | 31 +++++++++++++++++++++++++++++++
1 file changed, 31 insertions(+)
diff --git a/libavcodec/videotoolboxenc.c b/libavcodec/videotoolboxenc.c
index ec69bb1..07577b6 100644
--- a/libavcodec/videotoolboxenc.c
+++ b/libavcodec/videotoolboxenc.c
@@ -41,6 +41,12 @@ typedef enum VT_H264Profile {
H264_PROF_COUNT
} VT_H264Profile;
+typedef enum VTH264Entropy{
+ VT_ENTROPY_NOT_SET,
+ VT_CAVLC,
+ VT_CABAC
+} VTH264Entropy;
+
static const uint8_t start_code[] = { 0, 0, 0, 1 };
typedef struct BufNode {
@@ -69,6 +75,7 @@ typedef struct VTEncContext {
int64_t profile;
int64_t level;
+ int64_t entropy;
#if !TARGET_OS_IPHONE
int64_t allow_sw;
@@ -627,6 +634,11 @@ static av_cold int vtenc_init(AVCodecContext *avctx)
vtctx->has_b_frames = false;
}
+ if (vtctx->entropy == VT_CABAC && vtctx->profile == H264_PROF_BASELINE) {
+ av_log(avctx, AV_LOG_WARNING, "CABAC entropy requires 'main' or 'high'
profile, but baseline was requested. Encode will not use CABAC entropy.\n");
+ vtctx->entropy = VT_ENTROPY_NOT_SET;
+ }
+
if (!get_vt_profile_level(avctx, &profile_level)) return AVERROR(EINVAL);
vtctx->session = NULL;
@@ -736,6 +748,21 @@ static av_cold int vtenc_init(AVCodecContext *avctx)
}
}
+ if (vtctx->entropy != VT_ENTROPY_NOT_SET) {
+ CFStringRef entropy = vtctx->entropy == VT_CABAC ?
+ kVTH264EntropyMode_CABAC:
+ kVTH264EntropyMode_CAVLC;
+
+ status = VTSessionSetProperty(vtctx->session,
+
kVTCompressionPropertyKey_H264EntropyMode,
+ entropy);
+
+ if (status) {
+ av_log(avctx, AV_LOG_ERROR, "Error setting entropy property:
%d\n", status);
+ return AVERROR_EXTERNAL;
+ }
+ }
+
status = VTCompressionSessionPrepareToEncodeFrames(vtctx->session);
if (status) {
av_log(avctx, AV_LOG_ERROR, "Error: cannot prepare encoder: %d\n",
status);
@@ -1484,6 +1511,10 @@ static const AVOption options[] = {
{ .i64 = -1 }, -1, 1, VE },
#endif
+ { "entropy", "Entropy coding", OFFSET(entropy), AV_OPT_TYPE_INT, { .i64 =
VT_ENTROPY_NOT_SET }, VT_ENTROPY_NOT_SET, VT_CABAC, VE, "entropy" },
+ { "cavlc", "CAVLC entropy coding", 0, AV_OPT_TYPE_CONST, { .i64 = VT_CAVLC
}, INT_MIN, INT_MAX, VE, "entropy" },
+ { "cabac", "CABAC entropy coding", 0, AV_OPT_TYPE_CONST, { .i64 = VT_CABAC
}, INT_MIN, INT_MAX, VE, "entropy" },
+
{ NULL },
};
--
2.7.4
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