Hi,

thank you all for the fast feedback.
Regarding the GitHub references in the footer, I apologize for the overly 
promotional nature - that was not my intention. I was rushing to post and 
immediately realized it was excessive.

Regarding Lynne's suggestion about relocating functions from the detection box 
to the classify filter - I had considered this approach initially but kept the 
code in the detection box class since the classify filter file is already quite 
substantial. While these functions could theoretically be used elsewhere, that 
is unlikely. I am comfortable with either implementation approach.

I will fix the formatting issues in the patches promptly and move the code to 
the classify filter as suggested. Since most of the patches need correction, I 
will submit everything as a v2 patch set.

Kind regards​​​​​​​​​​​​​​​​
________________________________
From: ffmpeg-devel <ffmpeg-devel-boun...@ffmpeg.org> on behalf of Lynne 
<d...@lynne.ee>
Sent: Sunday, March 9, 2025 4:46:31 PM
To: ffmpeg-devel@ffmpeg.org <ffmpeg-devel@ffmpeg.org>
Subject: Re: [FFmpeg-devel] [PATCH FFmpeg 1/15] libavutil: add detectionbbox 
util functions

On 08/03/2025 15:58, m.kaindl0...@gmail.com wrote:
> Those functions will be used by classify in the upcoming patches.
>
> Try the new filters using my Github Repo 
> https://github.com/MaximilianKaindl/DeepFFMPEGVideoClassification.
>
> Any Feedback is appreciated!
>
> Signed-off-by: MaximilianKaindl <m.kaindl0...@gmail.com>
> ---
>   libavutil/detection_bbox.c | 54 ++++++++++++++++++++++++++++++++++++++
>   libavutil/detection_bbox.h | 31 ++++++++++++++++++++++
>   2 files changed, 85 insertions(+)
>
> diff --git a/libavutil/detection_bbox.c b/libavutil/detection_bbox.c index 
> cb157b355b..378233121d 100644
> --- a/libavutil/detection_bbox.c
> +++ b/libavutil/detection_bbox.c
> @@ -18,6 +18,7 @@
>
>   #include "detection_bbox.h"
>   #include "mem.h"
> +#include "libavutil/avstring.h"
>
>   AVDetectionBBoxHeader *av_detection_bbox_alloc(uint32_t nb_bboxes, size_t 
> *out_size)  { @@ -71,3 +72,56 @@ AVDetectionBBoxHeader 
> *av_detection_bbox_create_side_data(AVFrame *frame, uint32
>
>       return header;
>   }
> +
> +int av_detection_bbox_fill_with_best_labels(char **labels, float
> +*probabilities, int num_labels, AVDetectionBBox *bbox, int 
> max_classes_per_box, float confidence_threshold) {
> +    int i, j, minpos, ret;
> +    float min;
> +
> +    if (!labels || !probabilities || !bbox) {
> +        return AVERROR(EINVAL);
> +    }
> +
> +    for (i = 0; i < num_labels; i++) {
> +        if (probabilities[i] >= confidence_threshold) {
> +            if (bbox->classify_count >= max_classes_per_box) {
> +                // Find lowest probability classification
> +                min = av_q2d(bbox->classify_confidences[0]);
> +                minpos = 0;
> +                for (j = 1; j < bbox->classify_count; j++) {
> +                    float prob = av_q2d(bbox->classify_confidences[j]);
> +                    if (prob < min) {
> +                        min = prob;
> +                        minpos = j;
> +                    }
> +                }
> +
> +                if (probabilities[i] > min) {
> +                    ret = av_detection_bbox_set_content(bbox, labels[i], 
> minpos, probabilities[i]);
> +                    if (ret < 0)
> +                        return ret;
> +                }
> +            } else {
> +                ret = av_detection_bbox_set_content(bbox, labels[i], 
> bbox->classify_count, probabilities[i]);
> +                if (ret < 0)
> +                    return ret;
> +                bbox->classify_count++;
> +            }
> +        }
> +    }
> +    return 0;
> +}
> +
> +int av_detection_bbox_set_content(AVDetectionBBox *bbox, char *label,
> +int index, float probability) {
> +    // Set probability
> +    bbox->classify_confidences[index] = av_make_q((int)(probability *
> +10000), 10000);
> +
> +    // Copy label with size checking
> +    if (av_strlcpy(bbox->classify_labels[index], label, 
> AV_DETECTION_BBOX_LABEL_NAME_MAX_SIZE) >=
> +        AV_DETECTION_BBOX_LABEL_NAME_MAX_SIZE) {
> +        av_log(NULL, AV_LOG_WARNING, "Label truncated in 
> set_prob_and_label_of_bbox\n");
> +    }
> +
> +    return 0;
> +}
> diff --git a/libavutil/detection_bbox.h b/libavutil/detection_bbox.h index 
> 011988052c..27d749ad59 100644
> --- a/libavutil/detection_bbox.h
> +++ b/libavutil/detection_bbox.h
> @@ -105,4 +105,35 @@ AVDetectionBBoxHeader *av_detection_bbox_alloc(uint32_t 
> nb_bboxes, size_t *out_s
>    * AV_FRAME_DATA_DETECTION_BBOXES and initializes the variables.
>    */
>   AVDetectionBBoxHeader *av_detection_bbox_create_side_data(AVFrame *frame, 
> uint32_t nb_bboxes);
> +
> +/**
> + * Fills an AVDetectionBBox structure with the best labels based on 
> probabilities.
> + *
> + * This function selects up to max_classes_per_box labels with the
> +highest probabilities
> + * that exceed the given confidence threshold, and assigns them to the 
> bounding box.
> + *
> + * @param labels Array of label strings
> + * @param probabilities Array of probability values corresponding to
> +each label
> + * @param num_labels Number of elements in the labels and probabilities
> +arrays
> + * @param bbox Pointer to the AVDetectionBBox structure to be filled
> + * @param max_classes_per_box Maximum number of classes to assign to
> +the bounding box
> + * @param confidence_threshold Minimum probability value required for a
> +label to be considered
> + * @return 0 on success, negative error code on failure  */ int
> +av_detection_bbox_fill_with_best_labels(char **labels, float
> +*probabilities, int num_labels, AVDetectionBBox *bbox, int
> +max_classes_per_box, float confidence_threshold);
> +
> +/**
> + * Sets the content of an AVDetectionBBox at the specified index.
> + *
> + * This function assigns a label and its associated probability to the
> +specified index
> + * in the bounding box's internal storage.
> + *
> + * @param bbox Pointer to the AVDetectionBBox structure to modify
> + * @param label The class label to assign (will be copied internally)
> + * @param index The index at which to store the label and probability
> + * @param probability The confidence score/probability for this label
> + * @return 0 on success
> + */
> +int av_detection_bbox_set_content(AVDetectionBBox *bbox, char *label,
> +int index, float probability);

This is outside the scope of the file IMO. Not something that should be
in the public API.
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