From 8c9456042e0cd333702b8e77d3e80767a4c0b7cf Mon Sep 17 00:00:00 2001 From: Elias Carotti Date: Fri, 15 Sep 2023 20:05:43 +0200 Subject: [PATCH] avcodec/libx264: Add the SSE computation for libx264. Since libx264 only provides a per-frame per-channel PSNR, this is inverted to get back the SSE. --- libavcodec/libx264.c | 34 +++++++++++++++++++++++++++++++++- 1 file changed, 33 insertions(+), 1 deletion(-) diff --git a/libavcodec/libx264.c b/libavcodec/libx264.c index 77a9f173b4..85bd870f5d 100644 --- a/libavcodec/libx264.c +++ b/libavcodec/libx264.c @@ -726,7 +726,39 @@ FF_ENABLE_DEPRECATION_WARNINGS pkt->flags |= AV_PKT_FLAG_KEY*pic_out.b_keyframe; if (ret) { - ff_side_data_set_encoder_stats(pkt, (pic_out.i_qpplus1 - 1) * FF_QP2LAMBDA, NULL, 0, pict_type); + const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(csp_to_pixfmt(pic_out.img.i_csp)); + int error_count = 0; + int64_t *errors = NULL; + int64_t sse[3] = {0}; + + if (ctx->flags & AV_CODEC_FLAG_PSNR) { + double scale[3] = { 1, + (double)(1 << pix_desc->log2_chroma_h) * (1 << pix_desc->log2_chroma_w), + (double)(1 << pix_desc->log2_chroma_h) * (1 << pix_desc->log2_chroma_w), + }; + + error_count = pix_desc->nb_components; + + av_log(ctx, AV_LOG_DEBUG, "PSNR values from libx264: %.3f %.3f %.3f.\n", + pic_out.prop.f_psnr[0], pic_out.prop.f_psnr[1], pic_out.prop.f_psnr[2]); + + for (int i = 0; i < pix_desc->nb_components; ++i) { + double max_value = (double)(1 << pix_desc->comp[i].depth) - 1.0; + double plane_size = ctx->width * (double)ctx->height / scale[i]; + + /* psnr = 10 * log10(max_value * max_value / mse) */ + double mse = (max_value * max_value) / pow(10, pic_out.prop.f_psnr[i] / 10.0); + + /* SSE = MSE * width * height / scale -> because of possible chroma downsampling */ + sse[i] = (int64_t)floor(mse * plane_size + .5); + }; + + errors = sse; + } + + ff_side_data_set_encoder_stats(pkt, (pic_out.i_qpplus1 - 1) * FF_QP2LAMBDA, + errors, error_count, pict_type); + if (wallclock) ff_side_data_set_prft(pkt, wallclock); } -- 2.34.1