mirror of https://git.videolan.org/git/ffmpeg.git
avcodec/aom_film_grain: implement AFGS1 parsing
Based on the AOMedia Film Grain Synthesis 1 (AFGS1) spec: https://aomediacodec.github.io/afgs1-spec/ The parsing has been changed substantially relative to the AV1 film grain OBU. In particular: 1. There is the possibility of maintaining multiple independent film grain parameter sets, and decoders/players are recommended to pick the one most appropriate for the intended display resolution. This could also be used to e.g. switch between different grain profiles without having to re-signal the appropriate coefficients. 2. Supporting this, it's possible to *predict* the grain coefficients from previously signalled parameter sets, transmitting only the residual. 3. When not predicting, the parameter sets are now stored as a series of increments, rather than being directly transmitted. 4. There are several new AFGS1-exclusive fields. I placed this parser in its own file, rather than h2645_sei.c, since nothing in the generic AFGS1 film grain payload is specific to T.35, and to compartmentalize the code base.
This commit is contained in:
Niklas Haas
parent
1535d33818
commit
f50382cba6
|
|
@ -29,6 +29,7 @@
|
|||
#include "libavutil/imgutils.h"
|
||||
|
||||
#include "aom_film_grain.h"
|
||||
#include "get_bits.h"
|
||||
|
||||
// Common/shared helpers (not dependent on BIT_DEPTH)
|
||||
static inline int get_random_number(const int bits, unsigned *const state) {
|
||||
|
|
@ -118,6 +119,243 @@ int ff_aom_apply_film_grain(AVFrame *out, const AVFrame *in,
|
|||
return AVERROR_INVALIDDATA;
|
||||
}
|
||||
|
||||
int ff_aom_parse_film_grain_sets(AVFilmGrainAFGS1Params *s,
|
||||
const uint8_t *payload, int payload_size)
|
||||
{
|
||||
GetBitContext gbc, *gb = &gbc;
|
||||
AVFilmGrainAOMParams *aom;
|
||||
AVFilmGrainParams *fgp, *ref = NULL;
|
||||
int ret, num_sets, n, i, uv, num_y_coeffs, update_grain, luma_only;
|
||||
|
||||
ret = init_get_bits8(gb, payload, payload_size);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
s->enable = get_bits1(gb);
|
||||
if (!s->enable)
|
||||
return 0;
|
||||
|
||||
skip_bits(gb, 4); // reserved
|
||||
num_sets = get_bits(gb, 3) + 1;
|
||||
for (n = 0; n < num_sets; n++) {
|
||||
int payload_4byte, payload_size, set_idx, apply_units_log2, vsc_flag;
|
||||
int predict_scaling, predict_y_scaling, predict_uv_scaling[2];
|
||||
int payload_bits, start_position;
|
||||
|
||||
start_position = get_bits_count(gb);
|
||||
payload_4byte = get_bits1(gb);
|
||||
payload_size = get_bits(gb, payload_4byte ? 2 : 8);
|
||||
set_idx = get_bits(gb, 3);
|
||||
fgp = &s->sets[set_idx];
|
||||
aom = &fgp->codec.aom;
|
||||
|
||||
fgp->type = get_bits1(gb) ? AV_FILM_GRAIN_PARAMS_AV1 : AV_FILM_GRAIN_PARAMS_NONE;
|
||||
if (!fgp->type)
|
||||
continue;
|
||||
|
||||
fgp->seed = get_bits(gb, 16);
|
||||
update_grain = get_bits1(gb);
|
||||
if (!update_grain)
|
||||
continue;
|
||||
|
||||
apply_units_log2 = get_bits(gb, 4);
|
||||
fgp->width = get_bits(gb, 12) << apply_units_log2;
|
||||
fgp->height = get_bits(gb, 12) << apply_units_log2;
|
||||
luma_only = get_bits1(gb);
|
||||
if (luma_only) {
|
||||
fgp->subsampling_x = fgp->subsampling_y = 0;
|
||||
} else {
|
||||
fgp->subsampling_x = get_bits1(gb);
|
||||
fgp->subsampling_y = get_bits1(gb);
|
||||
}
|
||||
|
||||
fgp->bit_depth_luma = fgp->bit_depth_chroma = 0;
|
||||
fgp->color_primaries = AVCOL_PRI_UNSPECIFIED;
|
||||
fgp->color_trc = AVCOL_TRC_UNSPECIFIED;
|
||||
fgp->color_space = AVCOL_SPC_UNSPECIFIED;
|
||||
fgp->color_range = AVCOL_RANGE_UNSPECIFIED;
|
||||
|
||||
vsc_flag = get_bits1(gb); // video_signal_characteristics_flag
|
||||
if (vsc_flag) {
|
||||
int cicp_flag;
|
||||
fgp->bit_depth_luma = get_bits(gb, 3) + 8;
|
||||
if (!luma_only)
|
||||
fgp->bit_depth_chroma = fgp->bit_depth_luma;
|
||||
cicp_flag = get_bits1(gb);
|
||||
if (cicp_flag) {
|
||||
fgp->color_primaries = get_bits(gb, 8);
|
||||
fgp->color_trc = get_bits(gb, 8);
|
||||
fgp->color_space = get_bits(gb, 8);
|
||||
fgp->color_range = get_bits1(gb) ? AVCOL_RANGE_JPEG : AVCOL_RANGE_MPEG;
|
||||
if (fgp->color_primaries > AVCOL_PRI_NB ||
|
||||
fgp->color_primaries == AVCOL_PRI_RESERVED ||
|
||||
fgp->color_primaries == AVCOL_PRI_RESERVED0 ||
|
||||
fgp->color_trc > AVCOL_TRC_NB ||
|
||||
fgp->color_trc == AVCOL_TRC_RESERVED ||
|
||||
fgp->color_trc == AVCOL_TRC_RESERVED0 ||
|
||||
fgp->color_space > AVCOL_SPC_NB ||
|
||||
fgp->color_space == AVCOL_SPC_RESERVED)
|
||||
goto error;
|
||||
}
|
||||
}
|
||||
|
||||
predict_scaling = get_bits1(gb);
|
||||
if (predict_scaling && (!ref || ref == fgp))
|
||||
goto error; // prediction must be from valid, different set
|
||||
|
||||
predict_y_scaling = predict_scaling ? get_bits1(gb) : 0;
|
||||
if (predict_y_scaling) {
|
||||
int y_scale, y_offset, bits_res;
|
||||
y_scale = get_bits(gb, 9) - 256;
|
||||
y_offset = get_bits(gb, 9) - 256;
|
||||
bits_res = get_bits(gb, 3);
|
||||
if (bits_res) {
|
||||
int res[14], pred, granularity;
|
||||
aom->num_y_points = ref->codec.aom.num_y_points;
|
||||
for (i = 0; i < aom->num_y_points; i++)
|
||||
res[i] = get_bits(gb, bits_res);
|
||||
granularity = get_bits(gb, 3);
|
||||
for (i = 0; i < aom->num_y_points; i++) {
|
||||
pred = ref->codec.aom.y_points[i][1];
|
||||
pred = ((pred * y_scale + 8) >> 4) + y_offset;
|
||||
pred += (res[i] - (1 << (bits_res - 1))) * granularity;
|
||||
aom->y_points[i][0] = ref->codec.aom.y_points[i][0];
|
||||
aom->y_points[i][1] = av_clip_uint8(pred);
|
||||
}
|
||||
}
|
||||
} else {
|
||||
aom->num_y_points = get_bits(gb, 4);
|
||||
if (aom->num_y_points > 14) {
|
||||
goto error;
|
||||
} else if (aom->num_y_points) {
|
||||
int bits_inc, bits_scaling;
|
||||
int y_value = 0;
|
||||
bits_inc = get_bits(gb, 3) + 1;
|
||||
bits_scaling = get_bits(gb, 2) + 5;
|
||||
for (i = 0; i < aom->num_y_points; i++) {
|
||||
y_value += get_bits(gb, bits_inc);
|
||||
if (y_value > UINT8_MAX)
|
||||
goto error;
|
||||
aom->y_points[i][0] = y_value;
|
||||
aom->y_points[i][1] = get_bits(gb, bits_scaling);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if (luma_only) {
|
||||
aom->chroma_scaling_from_luma = 0;
|
||||
aom->num_uv_points[0] = aom->num_uv_points[1] = 0;
|
||||
} else {
|
||||
aom->chroma_scaling_from_luma = get_bits1(gb);
|
||||
if (aom->chroma_scaling_from_luma) {
|
||||
aom->num_uv_points[0] = aom->num_uv_points[1] = 0;
|
||||
} else {
|
||||
for (uv = 0; uv < 2; uv++) {
|
||||
predict_uv_scaling[uv] = predict_scaling ? get_bits1(gb) : 0;
|
||||
if (predict_uv_scaling[uv]) {
|
||||
int uv_scale, uv_offset, bits_res;
|
||||
uv_scale = get_bits(gb, 9) - 256;
|
||||
uv_offset = get_bits(gb, 9) - 256;
|
||||
bits_res = get_bits(gb, 3);
|
||||
aom->uv_mult[uv] = ref->codec.aom.uv_mult[uv];
|
||||
aom->uv_mult_luma[uv] = ref->codec.aom.uv_mult_luma[uv];
|
||||
aom->uv_offset[uv] = ref->codec.aom.uv_offset[uv];
|
||||
if (bits_res) {
|
||||
int res[10], pred, granularity;
|
||||
aom->num_uv_points[uv] = ref->codec.aom.num_uv_points[uv];
|
||||
for (i = 0; i < aom->num_uv_points[uv]; i++)
|
||||
res[i] = get_bits(gb, bits_res);
|
||||
granularity = get_bits(gb, 3);
|
||||
for (i = 0; i < aom->num_uv_points[uv]; i++) {
|
||||
pred = ref->codec.aom.uv_points[uv][i][1];
|
||||
pred = ((pred * uv_scale + 8) >> 4) + uv_offset;
|
||||
pred += (res[i] - (1 << (bits_res - 1))) * granularity;
|
||||
aom->uv_points[uv][i][0] = ref->codec.aom.uv_points[uv][i][0];
|
||||
aom->uv_points[uv][i][1] = av_clip_uint8(pred);
|
||||
}
|
||||
}
|
||||
} else {
|
||||
int bits_inc, bits_scaling, uv_offset;
|
||||
int uv_value = 0;
|
||||
aom->num_uv_points[uv] = get_bits(gb, 4);
|
||||
if (aom->num_uv_points[uv] > 10)
|
||||
goto error;
|
||||
bits_inc = get_bits(gb, 3) + 1;
|
||||
bits_scaling = get_bits(gb, 2) + 5;
|
||||
uv_offset = get_bits(gb, 8);
|
||||
for (i = 0; i < aom->num_uv_points[uv]; i++) {
|
||||
uv_value += get_bits(gb, bits_inc);
|
||||
if (uv_value > UINT8_MAX)
|
||||
goto error;
|
||||
aom->uv_points[uv][i][0] = uv_value;
|
||||
aom->uv_points[uv][i][1] = get_bits(gb, bits_scaling) + uv_offset;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
aom->scaling_shift = get_bits(gb, 2) + 8;
|
||||
aom->ar_coeff_lag = get_bits(gb, 2);
|
||||
num_y_coeffs = 2 * aom->ar_coeff_lag * (aom->ar_coeff_lag + 1);
|
||||
if (aom->num_y_points) {
|
||||
int ar_bits = get_bits(gb, 2) + 5;
|
||||
for (i = 0; i < num_y_coeffs; i++)
|
||||
aom->ar_coeffs_y[i] = get_bits(gb, ar_bits) - (1 << (ar_bits - 1));
|
||||
}
|
||||
for (uv = 0; uv < 2; uv++) {
|
||||
if (aom->chroma_scaling_from_luma || aom->num_uv_points[uv]) {
|
||||
int ar_bits = get_bits(gb, 2) + 5;
|
||||
for (i = 0; i < num_y_coeffs + !!aom->num_y_points; i++)
|
||||
aom->ar_coeffs_uv[uv][i] = get_bits(gb, ar_bits) - (1 << (ar_bits - 1));
|
||||
}
|
||||
}
|
||||
aom->ar_coeff_shift = get_bits(gb, 2) + 6;
|
||||
aom->grain_scale_shift = get_bits(gb, 2);
|
||||
for (uv = 0; uv < 2; uv++) {
|
||||
if (aom->num_uv_points[uv] && !predict_uv_scaling[uv]) {
|
||||
aom->uv_mult[uv] = get_bits(gb, 8) - 128;
|
||||
aom->uv_mult_luma[uv] = get_bits(gb, 8) - 128;
|
||||
aom->uv_offset[uv] = get_bits(gb, 9) - 256;
|
||||
}
|
||||
}
|
||||
aom->overlap_flag = get_bits1(gb);
|
||||
aom->limit_output_range = get_bits1(gb);
|
||||
|
||||
// use first set as reference only if it was fully transmitted
|
||||
if (n == 0)
|
||||
ref = fgp;
|
||||
|
||||
payload_bits = get_bits_count(gb) - start_position;
|
||||
if (payload_bits > payload_size * 8)
|
||||
goto error;
|
||||
skip_bits(gb, payload_size * 8 - payload_bits);
|
||||
}
|
||||
return 0;
|
||||
|
||||
error:
|
||||
memset(s, 0, sizeof(*s));
|
||||
return AVERROR_INVALIDDATA;
|
||||
}
|
||||
|
||||
int ff_aom_attach_film_grain_sets(const AVFilmGrainAFGS1Params *s, AVFrame *frame)
|
||||
{
|
||||
AVFilmGrainParams *fgp;
|
||||
if (!s->enable)
|
||||
return 0;
|
||||
|
||||
for (int i = 0; i < FF_ARRAY_ELEMS(s->sets); i++) {
|
||||
if (s->sets[i].type != AV_FILM_GRAIN_PARAMS_AV1)
|
||||
continue;
|
||||
fgp = av_film_grain_params_create_side_data(frame);
|
||||
if (!fgp)
|
||||
return AVERROR(ENOMEM);
|
||||
memcpy(fgp, &s->sets[i], sizeof(*fgp));
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
// Taken from the AV1 spec. Range is [-2048, 2047], mean is 0 and stddev is 512
|
||||
static const int16_t gaussian_sequence[2048] = {
|
||||
56, 568, -180, 172, 124, -84, 172, -64, -900, 24, 820,
|
||||
|
|
|
|||
|
|
@ -30,9 +30,22 @@
|
|||
|
||||
#include "libavutil/film_grain_params.h"
|
||||
|
||||
typedef struct AVFilmGrainAFGS1Params {
|
||||
int enable;
|
||||
AVFilmGrainParams sets[8];
|
||||
} AVFilmGrainAFGS1Params;
|
||||
|
||||
// Synthesizes film grain on top of `in` and stores the result to `out`. `out`
|
||||
// must already have been allocated and set to the same size and format as `in`.
|
||||
int ff_aom_apply_film_grain(AVFrame *out, const AVFrame *in,
|
||||
const AVFilmGrainParams *params);
|
||||
|
||||
// Parse AFGS1 parameter sets from an ITU-T T.35 payload. Returns 0 on success,
|
||||
// or a negative error code.
|
||||
int ff_aom_parse_film_grain_sets(AVFilmGrainAFGS1Params *s,
|
||||
const uint8_t *payload, int payload_size);
|
||||
|
||||
// Attach all valid film grain param sets to `frame`.
|
||||
int ff_aom_attach_film_grain_sets(const AVFilmGrainAFGS1Params *s, AVFrame *frame);
|
||||
|
||||
#endif /* AVCODEC_AOM_FILM_GRAIN_H */
|
||||
|
|
|
|||
Loading…
Reference in New Issue