[FFmpeg-devel] [PATCH v5 3/9] avcodec/av1dec: support setup shear process
Fei Wang
fei.w.wang at intel.com
Tue Oct 12 11:23:58 EEST 2021
Defined in spec 7.11.3.6/7.11.3.7.
Signed-off-by: Fei Wang <fei.w.wang at intel.com>
---
libavcodec/av1dec.c | 98 +++++++++++++++++++++++++++++++++++++++++++++
libavcodec/av1dec.h | 1 +
2 files changed, 99 insertions(+)
diff --git a/libavcodec/av1dec.c b/libavcodec/av1dec.c
index a69808f7b6..db110c50c7 100644
--- a/libavcodec/av1dec.c
+++ b/libavcodec/av1dec.c
@@ -28,6 +28,34 @@
#include "internal.h"
#include "profiles.h"
+/**< same with Div_Lut defined in spec 7.11.3.7 */
+static const uint16_t div_lut[AV1_DIV_LUT_NUM] = {
+ 16384, 16320, 16257, 16194, 16132, 16070, 16009, 15948, 15888, 15828, 15768,
+ 15709, 15650, 15592, 15534, 15477, 15420, 15364, 15308, 15252, 15197, 15142,
+ 15087, 15033, 14980, 14926, 14873, 14821, 14769, 14717, 14665, 14614, 14564,
+ 14513, 14463, 14413, 14364, 14315, 14266, 14218, 14170, 14122, 14075, 14028,
+ 13981, 13935, 13888, 13843, 13797, 13752, 13707, 13662, 13618, 13574, 13530,
+ 13487, 13443, 13400, 13358, 13315, 13273, 13231, 13190, 13148, 13107, 13066,
+ 13026, 12985, 12945, 12906, 12866, 12827, 12788, 12749, 12710, 12672, 12633,
+ 12596, 12558, 12520, 12483, 12446, 12409, 12373, 12336, 12300, 12264, 12228,
+ 12193, 12157, 12122, 12087, 12053, 12018, 11984, 11950, 11916, 11882, 11848,
+ 11815, 11782, 11749, 11716, 11683, 11651, 11619, 11586, 11555, 11523, 11491,
+ 11460, 11429, 11398, 11367, 11336, 11305, 11275, 11245, 11215, 11185, 11155,
+ 11125, 11096, 11067, 11038, 11009, 10980, 10951, 10923, 10894, 10866, 10838,
+ 10810, 10782, 10755, 10727, 10700, 10673, 10645, 10618, 10592, 10565, 10538,
+ 10512, 10486, 10460, 10434, 10408, 10382, 10356, 10331, 10305, 10280, 10255,
+ 10230, 10205, 10180, 10156, 10131, 10107, 10082, 10058, 10034, 10010, 9986,
+ 9963, 9939, 9916, 9892, 9869, 9846, 9823, 9800, 9777, 9754, 9732,
+ 9709, 9687, 9664, 9642, 9620, 9598, 9576, 9554, 9533, 9511, 9489,
+ 9468, 9447, 9425, 9404, 9383, 9362, 9341, 9321, 9300, 9279, 9259,
+ 9239, 9218, 9198, 9178, 9158, 9138, 9118, 9098, 9079, 9059, 9039,
+ 9020, 9001, 8981, 8962, 8943, 8924, 8905, 8886, 8867, 8849, 8830,
+ 8812, 8793, 8775, 8756, 8738, 8720, 8702, 8684, 8666, 8648, 8630,
+ 8613, 8595, 8577, 8560, 8542, 8525, 8508, 8490, 8473, 8456, 8439,
+ 8422, 8405, 8389, 8372, 8355, 8339, 8322, 8306, 8289, 8273, 8257,
+ 8240, 8224, 8208, 8192
+};
+
static uint32_t inverse_recenter(int r, uint32_t v)
{
if (v > 2 * r)
@@ -97,6 +125,70 @@ static void read_global_param(AV1DecContext *s, int type, int ref, int idx)
-mx, mx + 1, r) << prec_diff) + round;
}
+static uint64_t round_two(uint64_t x, uint16_t n)
+{
+ if (n == 0)
+ return x;
+ return ((x + ((uint64_t)1 << (n - 1))) >> n);
+}
+
+static int64_t round_two_signed(int64_t x, uint16_t n)
+{
+ return ((x<0) ? -((int64_t)round_two(-x, n)) : (int64_t)round_two(x, n));
+}
+
+/**
+ * Resolve divisor process.
+ * see spec 7.11.3.7
+ */
+static int16_t resolve_divisor(uint32_t d, uint16_t *shift)
+{
+ int32_t e, f;
+
+ *shift = av_log2(d);
+ e = d - (1 << (*shift));
+ if (*shift > AV1_DIV_LUT_BITS)
+ f = round_two(e, *shift - AV1_DIV_LUT_BITS);
+ else
+ f = e << (AV1_DIV_LUT_BITS - (*shift));
+
+ *shift += AV1_DIV_LUT_PREC_BITS;
+
+ return div_lut[f];
+}
+
+/**
+ * check if global motion params is valid.
+ * see spec 7.11.3.6
+ */
+static uint8_t get_shear_params_valid(AV1DecContext *s, int idx)
+{
+ int16_t alpha, beta, gamma, delta, divf, divs;
+ int64_t v, w;
+ int32_t *param = &s->cur_frame.gm_params[idx][0];
+ if (param[2] < 0)
+ return 0;
+
+ alpha = av_clip_int16(param[2] - (1 << AV1_WARPEDMODEL_PREC_BITS));
+ beta = av_clip_int16(param[3]);
+ divf = resolve_divisor(abs(param[2]), &divs);
+ v = (int64_t)param[4] * (1 << AV1_WARPEDMODEL_PREC_BITS);
+ w = (int64_t)param[3] * param[4];
+ gamma = av_clip_int16((int)round_two_signed((v * divf), divs));
+ delta = av_clip_int16(param[5] - (int)round_two_signed((w * divf), divs) - (1 << AV1_WARPEDMODEL_PREC_BITS));
+
+ alpha = round_two_signed(alpha, AV1_WARP_PARAM_REDUCE_BITS) << AV1_WARP_PARAM_REDUCE_BITS;
+ beta = round_two_signed(beta, AV1_WARP_PARAM_REDUCE_BITS) << AV1_WARP_PARAM_REDUCE_BITS;
+ gamma = round_two_signed(gamma, AV1_WARP_PARAM_REDUCE_BITS) << AV1_WARP_PARAM_REDUCE_BITS;
+ delta = round_two_signed(delta, AV1_WARP_PARAM_REDUCE_BITS) << AV1_WARP_PARAM_REDUCE_BITS;
+
+ if ((4 * abs(alpha) + 7 * abs(beta)) >= (1 << AV1_WARPEDMODEL_PREC_BITS) ||
+ (4 * abs(gamma) + 4 * abs(delta)) >= (1 << AV1_WARPEDMODEL_PREC_BITS))
+ return 0;
+
+ return 1;
+}
+
/**
* update gm type/params, since cbs already implemented part of this funcation,
* so we don't need to full implement spec.
@@ -144,6 +236,9 @@ static void global_motion_params(AV1DecContext *s)
read_global_param(s, type, ref, 0);
read_global_param(s, type, ref, 1);
}
+ if (type <= AV1_WARP_MODEL_AFFINE) {
+ s->cur_frame.gm_invalid[ref] = !get_shear_params_valid(s, ref);
+ }
}
}
@@ -509,6 +604,9 @@ static int av1_frame_ref(AVCodecContext *avctx, AV1Frame *dst, const AV1Frame *s
dst->spatial_id = src->spatial_id;
dst->temporal_id = src->temporal_id;
+ memcpy(dst->gm_invalid,
+ src->gm_invalid,
+ AV1_NUM_REF_FRAMES * sizeof(uint8_t));
memcpy(dst->gm_type,
src->gm_type,
AV1_NUM_REF_FRAMES * sizeof(uint8_t));
diff --git a/libavcodec/av1dec.h b/libavcodec/av1dec.h
index 248a68750f..4e140588b9 100644
--- a/libavcodec/av1dec.h
+++ b/libavcodec/av1dec.h
@@ -42,6 +42,7 @@ typedef struct AV1Frame {
int temporal_id;
int spatial_id;
+ uint8_t gm_invalid[AV1_NUM_REF_FRAMES];
uint8_t gm_type[AV1_NUM_REF_FRAMES];
int32_t gm_params[AV1_NUM_REF_FRAMES][6];
--
2.25.1
More information about the ffmpeg-devel
mailing list