From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by master.gitmailbox.com (Postfix) with ESMTP id 9593549A17 for ; Mon, 26 Feb 2024 14:35:44 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 296AD68C825; Mon, 26 Feb 2024 16:35:33 +0200 (EET) Received: from haasn.dev (haasn.dev [78.46.187.166]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 65F7568BF54 for ; Mon, 26 Feb 2024 16:35:25 +0200 (EET) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=haasn.xyz; s=mail; t=1708958125; bh=j1ZbVLnvVRPq0XNYBvJT0aGVy6fuSO+arHg1u0hg8K0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rrpU3SSgv9mJWyLMJe0/qc0rN7SYG3GRUoPf5R0zOuyeEN6ZeXqadz75SBZjYX7zZ kswAe85s5dcmzzpB1zIsRw8rmmXLj82mcWCQmcRDI6VK6auOtdgnUZ2V06g6NM4ksm ggk1pyAmAVTtmTf/0r6T/laEdUTEKgtHwwjXTTdU= Received: from haasn.dev (unknown [10.30.0.2]) by haasn.dev (Postfix) with ESMTP id 33A404033C; Mon, 26 Feb 2024 15:35:25 +0100 (CET) From: Niklas Haas To: ffmpeg-devel@ffmpeg.org Date: Mon, 26 Feb 2024 15:35:12 +0100 Message-ID: <20240226143521.57913-2-ffmpeg@haasn.xyz> X-Mailer: git-send-email 2.43.2 In-Reply-To: <20240226143521.57913-1-ffmpeg@haasn.xyz> References: <20240226143521.57913-1-ffmpeg@haasn.xyz> MIME-Version: 1.0 Subject: [FFmpeg-devel] [PATCH 2/4] avcodec/aom_film_grain: implement AFGS1 X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Cc: Niklas Haas Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: From: Niklas Haas 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 are recommended to pick the one most appropriate for the intended display resolution. This is to support scalable / multi-level codecs, although 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. 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. Note: Due to an ambiguity/mistake in the specification, the parsing of AR coefficients is possibly incorrect. See for details: https://github.com/AOMediaCodec/afgs1-spec/issues/115 --- libavcodec/aom_film_grain.c | 227 ++++++++++++++++++++++++++++++++++++ libavcodec/aom_film_grain.h | 25 ++++ 2 files changed, 252 insertions(+) diff --git a/libavcodec/aom_film_grain.c b/libavcodec/aom_film_grain.c index 1bdaafc39f7..5614d3e8d16 100644 --- a/libavcodec/aom_film_grain.c +++ b/libavcodec/aom_film_grain.c @@ -29,6 +29,7 @@ #include "libavutil/imgutils.h" #include "aom_film_grain.h" +#include "get_bits.h" // Common/shared helpers (not dependent on BITDEPTH) static inline int get_random_number(const int bits, unsigned *const state) { @@ -96,6 +97,232 @@ int ff_aom_apply_film_grain(AVFrame *out, const AVFrame *in, return AVERROR_INVALIDDATA; } +int ff_aom_parse_film_grain_sets(AVFilmGrainAOMParamSets *s, + const uint8_t *payload, int payload_size) +{ + GetBitContext gbc, *gb = &gbc; + AVFilmGrainAOMParams *aom; + AVFilmGrainAOMParamSet *fgps, *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); + 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); + fgps = &s->sets[set_idx]; + + fgps->apply_grain = get_bits1(gb); + if (!fgps->apply_grain) + continue; + + fgps->grain_seed = get_bits(gb, 16); + update_grain = get_bits1(gb); + if (!update_grain) + continue; + + apply_units_log2 = get_bits(gb, 4); + fgps->apply_width = get_bits(gb, 12) << apply_units_log2; + fgps->apply_height = get_bits(gb, 12) << apply_units_log2; + luma_only = get_bits1(gb); + if (luma_only) { + fgps->subx = fgps->suby = 0; + } else { + fgps->subx = get_bits1(gb); + fgps->suby = get_bits1(gb); + } + + vsc_flag = get_bits1(gb); // video_signal_characteristics_flag + if (vsc_flag) { + int cicp_flag; + skip_bits(gb, 3); // bit_depth_minus8 + cicp_flag = get_bits1(gb); + if (cicp_flag) + skip_bits(gb, 8 + 8 + 8 + 1); // cicp_info + } + + aom = &fgps->params; + predict_scaling = get_bits1(gb); + if (predict_scaling && (!ref || ref == fgps)) + 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->params.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->params.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->params.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->params.uv_mult[uv]; + aom->uv_mult_luma[uv] = ref->params.uv_mult_luma[uv]; + aom->uv_offset[uv] = ref->params.uv_offset[uv]; + if (bits_res) { + int res[10], pred, granularity; + aom->num_uv_points[uv] = ref->params.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->params.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->params.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 = fgps; + + 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: + s->enable = 0; + return AVERROR_INVALIDDATA; +} + +const AVFilmGrainAOMParamSet *ff_aom_select_film_grain_set(const AVFilmGrainAOMParamSets *s, + const AVFrame *frame) +{ + const AVFilmGrainAOMParamSet *fgps, *best; + const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(frame->format); + if (!s->enable || !desc) + return NULL; + + best = NULL; + for (int i = 0; i < 8; i++) { + fgps = &s->sets[i]; + if (!fgps->apply_width || + !fgps->apply_height || + fgps->apply_width > frame->width || + fgps->apply_height > frame->height || + fgps->subx != desc->log2_chroma_w || + fgps->suby != desc->log2_chroma_h) + continue; + + if (!best || + fgps->apply_width > best->apply_width || + fgps->apply_height > best->apply_height) + best = fgps; + } + + return best; +} + // 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, diff --git a/libavcodec/aom_film_grain.h b/libavcodec/aom_film_grain.h index 5d772bd7d17..b985451dbc3 100644 --- a/libavcodec/aom_film_grain.h +++ b/libavcodec/aom_film_grain.h @@ -30,9 +30,34 @@ #include "libavutil/film_grain_params.h" +// Stand-alone AFGS1 metadata parameter set +typedef struct AVFilmGrainAOMParamSet { + int apply_grain; + int apply_width; + int apply_height; + int subx, suby; + uint16_t grain_seed; + AVFilmGrainAOMParams params; +} AVFilmGrainAOMParamSet; + +typedef struct AVFilmGrainAOMParamSets { + int enable; + AVFilmGrainAOMParamSet sets[8]; +} AVFilmGrainAOMParamSets; + // 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(AVFilmGrainAOMParamSets *s, + const uint8_t *payload, int payload_size); + +// Select the most appropriate film grain parameter set for a given +// frame. Returns the parameter set, or NULL if none was selected. +const AVFilmGrainAOMParamSet *ff_aom_select_film_grain_set(const AVFilmGrainAOMParamSets *s, + const AVFrame *frame); + #endif /* AVCODEC_AOM_FILM_GRAIN_H */ -- 2.43.2 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".