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 ESMTPS id C3EFA44876 for ; Sat, 18 Jan 2025 20:20:11 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id CF4A768B398; Sat, 18 Jan 2025 22:19:56 +0200 (EET) Received: from relay1-d.mail.gandi.net (relay1-d.mail.gandi.net [217.70.183.193]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id AF17D68B224 for ; Sat, 18 Jan 2025 22:19:49 +0200 (EET) Received: by mail.gandi.net (Postfix) with ESMTPSA id EC414240002 for ; Sat, 18 Jan 2025 20:19:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=niedermayer.cc; s=gm1; t=1737231589; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=WCGvHDBREynazPHbvvKf6uoTratxvZxIN2+HMc0igkE=; b=TBWFXXmdrt9/DEuSWM5BcZBd95XsAMflw9O4SXxsmmhESdVjDasYZX1ltOd8cr3rSNfvYm 7ftnMye6ThOaAKFoYNtv+dH9fafdQ37l7UDdW5Xt/Adp10D74UXHXNPbWeZs0NG/oz8Dcl 8hmp1t9jbwZoYMq9Zoc/oOdFXrC6ervYJnBAl1cCNPqAgPK9p9M/z8XEvAyMSFdjiUNjmS oNcLLy9J+jYKB06WlaDYfpJo0ze6Z0LTmy7+OKJD0HVhSw36pW3fU7O+ef/8cN1m2VpFpk iNHOmBNY99IRRePEW0jmsN3YgZz6RO4479oHfskM/G3tqh/3qNJT+/Gw6ZafWA== From: Michael Niedermayer To: FFmpeg development discussions and patches Date: Sat, 18 Jan 2025 21:19:46 +0100 Message-ID: <20250118201946.2389042-2-michael@niedermayer.cc> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250118201946.2389042-1-michael@niedermayer.cc> References: <20250118201946.2389042-1-michael@niedermayer.cc> MIME-Version: 1.0 X-GND-Sasl: michael@niedermayer.cc Subject: [FFmpeg-devel] [PATCH 2/2] avcodec/ffv1: Compactify floats 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 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: float16 (and more so float32) have many odd values half the values are negative, many are larger than "1.0" and many values are very close to 0. Storing the 16bits as is, looses compression because of the mixture of dense and sparse regions and also many completely unused ones. This simply remaps the 65536 values so no unused values remain This improves compression by about 1% for the ACES_OT_VWG_SampleFrames testset (this testset contains all kind of funny values including many images with negative rgb values) The space needed for the map is insignificant compared to the compression gained Sponsored-by: Sovereign Tech Fund Signed-off-by: Michael Niedermayer --- libavcodec/ffv1.h | 1 + libavcodec/ffv1dec_template.c | 20 +++++++++++++ libavcodec/ffv1enc_template.c | 54 +++++++++++++++++++++++++++++++++++ 3 files changed, 75 insertions(+) diff --git a/libavcodec/ffv1.h b/libavcodec/ffv1.h index 2c2df154037..bf49f613a75 100644 --- a/libavcodec/ffv1.h +++ b/libavcodec/ffv1.h @@ -104,6 +104,7 @@ typedef struct FFV1SliceContext { uint64_t (*rc_stat2[MAX_QUANT_TABLES])[32][2]; }; }; + uint16_t fltmap[4][65536]; } FFV1SliceContext; typedef struct FFV1Context { diff --git a/libavcodec/ffv1dec_template.c b/libavcodec/ffv1dec_template.c index 0be17b54bbb..4662ec51651 100644 --- a/libavcodec/ffv1dec_template.c +++ b/libavcodec/ffv1dec_template.c @@ -155,6 +155,20 @@ static int RENAME(decode_rgb_frame)(FFV1Context *f, FFV1SliceContext *sc, memset(RENAME(sc->sample_buffer), 0, 8 * (w + 6) * sizeof(*RENAME(sc->sample_buffer))); + if (f->flt) { + for (int p= 0; p<3 + transparency; p++) { + int j = 0; + int lu = 0; + uint8_t state[2] = {128, 128}; + for (int i= 0; i<65536; i++) { + int u = get_rac(&sc->c, state + lu); + sc->fltmap[p][j] = i; + j+= u; + lu = u; + } + } + } + for (y = 0; y < h; y++) { for (p = 0; p < 3 + transparency; p++) { int ret; @@ -186,6 +200,12 @@ static int RENAME(decode_rgb_frame)(FFV1Context *f, FFV1SliceContext *sc, r += g; } if (f->flt) { + r = sc->fltmap[0][r]; + g = sc->fltmap[1][g]; + b = sc->fltmap[2][b]; + if (transparency) + a = sc->fltmap[3][a]; + if (!(r&0x8000)) r ^= 0x7FFF; if (!(g&0x8000)) diff --git a/libavcodec/ffv1enc_template.c b/libavcodec/ffv1enc_template.c index 4d20cb93627..da81a6a44ac 100644 --- a/libavcodec/ffv1enc_template.c +++ b/libavcodec/ffv1enc_template.c @@ -148,6 +148,54 @@ static int RENAME(encode_rgb_frame)(FFV1Context *f, FFV1SliceContext *sc, memset(RENAME(sc->sample_buffer), 0, ring_size * MAX_PLANES * (w + 6) * sizeof(*RENAME(sc->sample_buffer))); + if (f->flt) { + memset(sc->fltmap, 0, sizeof(sc->fltmap)); + + for (y = 0; y < h; y++) { + for (x = 0; x < w; x++) { + int b, g, r, av_uninit(a); + + if (sizeof(TYPE) == 4 || transparency) { + g = *((const uint16_t *)(src[0] + x*2 + stride[0]*y)); + b = *((const uint16_t *)(src[1] + x*2 + stride[1]*y)); + r = *((const uint16_t *)(src[2] + x*2 + stride[2]*y)); + if (transparency) + a = *((const uint16_t *)(src[3] + x*2 + stride[3]*y)); + } else { + b = *((const uint16_t *)(src[0] + x*2 + stride[0]*y)); + g = *((const uint16_t *)(src[1] + x*2 + stride[1]*y)); + r = *((const uint16_t *)(src[2] + x*2 + stride[2]*y)); + } + if (!(r&0x8000)) + r ^= 0x7FFF; + if (!(g&0x8000)) + g ^= 0x7FFF; + if (!(b&0x8000)) + b ^= 0x7FFF; + if (transparency && !(a&0x8000)) + a ^= 0x7FFF; + + sc->fltmap[0][r] = 1; + sc->fltmap[1][g] = 1; + sc->fltmap[2][b] = 1; + if (transparency) + sc->fltmap[3][a] = 1; + } + } + for (int p= 0; p<3 + transparency; p++) { + int j = 0; + int lu = 0; + uint8_t state[2] = {128, 128}; + for (int i= 0; i<65536; i++) { + int u = sc->fltmap[p][i]; + sc->fltmap[p][i] = j; + j+= u; + put_rac(&sc->c, state + lu, u); + lu = u; + } + } + } + for (y = 0; y < h; y++) { for (i = 0; i < ring_size; i++) for (p = 0; p < MAX_PLANES; p++) @@ -189,6 +237,12 @@ static int RENAME(encode_rgb_frame)(FFV1Context *f, FFV1SliceContext *sc, b ^= 0x7FFF; if (transparency && !(a&0x8000)) a ^= 0x7FFF; + + r = sc->fltmap[0][r]; + g = sc->fltmap[1][g]; + b = sc->fltmap[2][b]; + if (transparency) + a = sc->fltmap[3][a]; } if (sc->slice_coding_mode != 1) { -- 2.48.1 _______________________________________________ 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".