From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ffbox0-bg.ffmpeg.org (ffbox0-bg.ffmpeg.org [79.124.17.100]) by master.gitmailbox.com (Postfix) with ESMTPS id DD3594F6BE for ; Fri, 20 Jun 2025 14:15:49 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.ffmpeg.org (Postfix) with ESMTP id DF4BB68DC98; Fri, 20 Jun 2025 17:15:33 +0300 (EEST) Received: from haasn.dev (haasn.dev [78.46.187.166]) by ffbox0-bg.ffmpeg.org (Postfix) with ESMTP id 87E7168DC54 for ; Fri, 20 Jun 2025 17:15:26 +0300 (EEST) Received: from haasn.dev (unknown [10.30.1.1]) by haasn.dev (Postfix) with UTF8SMTP id 3D3984296E; Fri, 20 Jun 2025 16:15:26 +0200 (CEST) From: Niklas Haas To: ffmpeg-devel@ffmpeg.org Date: Fri, 20 Jun 2025 16:13:33 +0200 Message-ID: <20250620141524.2459797-2-ffmpeg@haasn.xyz> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250620141524.2459797-1-ffmpeg@haasn.xyz> References: <20250620141524.2459797-1-ffmpeg@haasn.xyz> MIME-Version: 1.0 Subject: [FFmpeg-devel] [PATCH v2 1/2] avfilter/vf_thumbnail: support more planar formats 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 This adds support for high bit depth formats, as well as formats with fewer than 3 planes. The implementation for HBD is the same as for 8 bit formats, just right shifted to 8 bits. It's worth pointing out that this also works for HDR formats (and even DV), because the underlying implementation is just trying to minimize the histogram difference. If anything, using a HDR format will result in a *more* accurate detection, because HDR formats tend to be more perceptually uniform. --- libavfilter/vf_thumbnail.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) diff --git a/libavfilter/vf_thumbnail.c b/libavfilter/vf_thumbnail.c index 90125a879c..55a0598e50 100644 --- a/libavfilter/vf_thumbnail.c +++ b/libavfilter/vf_thumbnail.c @@ -53,6 +53,8 @@ typedef struct ThumbContext { int planewidth[4]; int planeheight[4]; + int planes; + int bitdepth; } ThumbContext; #define OFFSET(x) offsetof(ThumbContext, x) @@ -194,7 +196,7 @@ static int do_slice(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs) } break; default: - for (int plane = 0; plane < 3; plane++) { + for (int plane = 0; plane < s->planes; plane++) { const int slice_start = (s->planeheight[plane] * jobnr) / nb_jobs; const int slice_end = (s->planeheight[plane] * (jobnr+1)) / nb_jobs; const uint8_t *p = frame->data[plane] + slice_start * frame->linesize[plane]; @@ -202,10 +204,21 @@ static int do_slice(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs) const int planewidth = s->planewidth[plane]; int *hhist = hist + 256 * plane; - for (int j = slice_start; j < slice_end; j++) { - for (int i = 0; i < planewidth; i++) - hhist[p[i]]++; - p += linesize; + if (s->bitdepth > 8) { + const uint16_t *p16 = (const uint16_t *) p; + const int shift = s->bitdepth - 8; + + for (int j = slice_start; j < slice_end; j++) { + for (int i = 0; i < planewidth; i++) + hhist[(p16[i] >> shift) & 0xFF]++; + p16 += linesize >> 1; + } + } else { + for (int j = slice_start; j < slice_end; j++) { + for (int i = 0; i < planewidth; i++) + hhist[p[i]]++; + p += linesize; + } } } break; @@ -286,6 +299,8 @@ static int config_props(AVFilterLink *inlink) s->planewidth[0] = s->planewidth[3] = inlink->w; s->planeheight[1] = s->planeheight[2] = AV_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h); s->planeheight[0] = s->planeheight[3] = inlink->h; + s->planes = av_pix_fmt_count_planes(inlink->format) - !!(desc->flags & AV_PIX_FMT_FLAG_ALPHA); + s->bitdepth = desc->comp[0].depth; return 0; } -- 2.49.0 _______________________________________________ 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".