Assertion failed in stbir__normalize_downsample_coefficients()

Hi, I was trying to benchmark image resizing and ran into an issue. With certain parameters, stbir_resize_uint8_generic() will fail an assertion and abort. The following program triggers it here:

#include <stdlib.h>

#define STB_IMAGE_RESIZE_IMPLEMENTATION
#include "stb_image_resize.h"

#define IN_W 2000
#define IN_H 2000
#define OUT_W 1304
#define OUT_H 1304

int
main (int argc, char *argv [])
{
    void *in = calloc (IN_W * IN_H, 4);
    void *out = malloc (OUT_W * OUT_H * 4);

    stbir_resize_uint8_generic (in, IN_W, IN_H, 0,
                                out, OUT_W, OUT_H, 0,
                                4, 0, STBIR_FLAG_ALPHA_PREMULTIPLIED,
                                STBIR_EDGE_ZERO,
                                STBIR_FILTER_TRIANGLE,
                                STBIR_COLORSPACE_LINEAR,
                                NULL);
    return 0;
}

Output:

$ gcc -g -lm stbir-test-case.c -o stbir-test-case
$ ./stbir-test-case 
stbir-test-case: stb_image_resize.h:1150: stbir__normalize_downsample_coefficients: Assertion `total < 1.1f' failed.
Aborted (core dumped)

Trace:

#0  0x00007ffff7d296bc in __pthread_kill_implementation ()
   from /lib64/libc.so.6
#1  0x00007ffff7cd66f6 in raise () from /lib64/libc.so.6
#2  0x00007ffff7cbf814 in abort () from /lib64/libc.so.6
#3  0x00007ffff7cbf72b in __assert_fail_base.cold () from /lib64/libc.so.6
#4  0x00007ffff7cceb26 in __assert_fail () from /lib64/libc.so.6
#5  0x000000000040240e in stbir__normalize_downsample_coefficients (
    contributors=0x7ffff6687010, coefficients=0x7ffff668aeb0, 
    filter=STBIR_FILTER_TRIANGLE, scale_ratio=0.65200001, input_size=2000, 
    output_size=1304)
    at stb_image_resize.h:1150
#6  0x0000000000402908 in stbir__calculate_filters (
    contributors=0x7ffff6687010, coefficients=0x7ffff668aeb0, 
    filter=STBIR_FILTER_TRIANGLE, scale_ratio=0.65200001, shift=0, 
    input_size=2000, output_size=1304)
    at stb_image_resize.h:1239
#7  0x000000000040726d in stbir__resize_allocated (info=0x7fffffffd8a0, 
    input_data=0x7ffff6d3b010, input_stride_in_bytes=0, 
    output_data=0x7ffff66be010, output_stride_in_bytes=0, alpha_channel=0, 
    flags=1, type=STBIR_TYPE_UINT8, edge_horizontal=STBIR_EDGE_ZERO, 
    edge_vertical=STBIR_EDGE_ZERO, colorspace=STBIR_COLORSPACE_LINEAR, 
    tempmem=0x7ffff6687010, tempmem_size_in_bytes=221376)
    at stb_image_resize.h:2405
#8  0x000000000040743a in stbir__resize_arbitrary (alloc_context=0x0, 
    input_data=0x7ffff6d3b010, input_w=2000, input_h=2000, 
    input_stride_in_bytes=0, output_data=0x7ffff66be010, output_w=1304, 
    output_h=1304, output_stride_in_bytes=0, s0=0, t0=0, s1=1, t1=1, 
    transform=0x0, channels=4, alpha_channel=0, flags=1, 
    type=STBIR_TYPE_UINT8, h_filter=STBIR_FILTER_TRIANGLE, 
    v_filter=STBIR_FILTER_TRIANGLE, edge_horizontal=STBIR_EDGE_ZERO, 
    edge_vertical=STBIR_EDGE_ZERO, colorspace=STBIR_COLORSPACE_LINEAR)
    at stb_image_resize.h:2451
#9  0x000000000040771f in stbir_resize_uint8_generic (
    input_pixels=0x7ffff6d3b010 "", input_w=2000, input_h=2000, 
    input_stride_in_bytes=0, output_pixels=0x7ffff66be010 "", output_w=1304, 
    output_h=1304, output_stride_in_bytes=0, num_channels=4, alpha_channel=0, 
    flags=1, edge_wrap_mode=STBIR_EDGE_ZERO, filter=STBIR_FILTER_TRIANGLE, 
    space=STBIR_COLORSPACE_LINEAR, alloc_context=0x0)
    at stb_image_resize.h:2509
#10 0x0000000000407b25 in main (argc=1, 
    argv=0x7fffffffdc08 "\364\340\377\377\377\177") at stbir-test-case.c:17

nothings / stb

Assertion failed in stbir__normalize_downsample_coefficients() #1449