From a6c363e8dac1e0fd932b1a17838e0da3b13f3b4c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Kacper=20Michaj=C5=82ow?= Date: Fri, 4 Oct 2024 04:17:15 +0200 Subject: [PATCH] f_hwtransfer: fix too aggressive preference to use direct upload format Well, this was thinko on last minute code simplification I made. We need to check both input and output formats. --- filters/f_hwtransfer.c | 27 ++++++++++++++++----------- 1 file changed, 16 insertions(+), 11 deletions(-) diff --git a/filters/f_hwtransfer.c b/filters/f_hwtransfer.c index ca53094446..f39a28f749 100644 --- a/filters/f_hwtransfer.c +++ b/filters/f_hwtransfer.c @@ -129,18 +129,23 @@ static bool select_format(struct priv *p, int input_fmt, int *upload_fmts = &p->upload_fmts[p->fmt_upload_index[index]]; int num_upload_fmts = p->fmt_upload_num[index]; - // Select the output format as the upload format if available to avoid double - // conversion. Note that this will prevent double conversion but does not - // guarantee that the conversion chain is optimal. Conversion during upload - // might already be done on hardware, in which case it may be better to - // prefer a lighter conversion before upload, instead of going directly to - // the output format. However, such cases are uncommon, and in practice, - // there is no good way to predict this without hardcoding specific rules. - int hw_input_fmt = mp_imgfmt_select_best_list(upload_fmts, num_upload_fmts, hw_output_fmt); + // Select the best input format from the available upload formats. + int hw_input_fmt = mp_imgfmt_select_best_list(upload_fmts, num_upload_fmts, input_fmt); + + // If the input format is not directly uploadable, conversion will be needed. + // Attempt to convert directly to the output format to avoid double conversion. + if (input_fmt != hw_input_fmt) { + int upload_output_fmt = mp_imgfmt_select_best_list(upload_fmts, num_upload_fmts, hw_output_fmt); + // Use this format only if it avoids double conversion, i.e., if we can + // upload the output format directly. If that's not the case, just use + // the best format for the input format selected earlier, as double + // conversion is unavoidable anyway. This approach prefers a closer + // conversion before upload and do remaining conversion during upload, + // which may be hardware-accelerated. + if (upload_output_fmt == hw_output_fmt) + hw_input_fmt = upload_output_fmt; + } - // Select best input format for the available upload formats otherwise. - if (hw_input_fmt != hw_output_fmt) - hw_input_fmt = mp_imgfmt_select_best_list(upload_fmts, num_upload_fmts, input_fmt); if (!hw_input_fmt) return false;