How to use ffmpeg on hardware acceleration with multiple inputs? - ffmpeg

Question

I'm trying to speed up the rendering of a video by using the GPU instead of the CPU. This code works, but I don't know if I'm doing it correctly.
ffmpeg -hwaccel cuvid -c:v hevc_cuvid \
-i video.mp4 \
-i logo.png \
-i text.mov \
-c:v h264_nvenc \
-filter_complex " \
[0]scale_npp=1920:1080,hwdownload,format=nv12[bg0]; \
[bg0]trim=0.00:59.460,setpts=PTS-STARTPTS[bg0]; \
[1]scale=150:-1[logo1];[bg0][logo1]overlay=(W-w)-10:(H-h)-10[bg0]; \
[2]scale=500:-1[logo2];[logo2]setpts=PTS-STARTPTS[logo2]; \
[bg0][logo2]overlay=-150:-100[bg0]; \
[bg0]fade=in:00:30,fade=out:1750:30[bg0]" \
-map "[bg0]" -preset fast -y output.mp4
I feel like I need to be using hwuplaod somewhere in there, but I'm not totally sure. Any help would be appreciated.
Log from run:
ffmpeg version 4.0 Copyright (c) 2000-2018 the FFmpeg developers
built with gcc 5.4.0 (Ubuntu 5.4.0-6ubuntu1~16.04.11) 20160609
configuration: --enable-gpl --enable-libx264 --enable-cuda --enable-nvenc --enable-cuvid --enable-nonfree --enable-libnpp --extra-cflags=-I/usr/local/cuda/include/ --extra-ldflags=-L/usr/local/cuda/lib64/
libavutil 56. 14.100 / 56. 14.100
libavcodec 58. 18.100 / 58. 18.100
libavformat 58. 12.100 / 58. 12.100
libavdevice 58. 3.100 / 58. 3.100
libavfilter 7. 16.100 / 7. 16.100
libswscale 5. 1.100 / 5. 1.100
libswresample 3. 1.100 / 3. 1.100
libpostproc 55. 1.100 / 55. 1.100
[hevc # 0x3eb04c0] vps_num_hrd_parameters -1 is invalid
[hevc # 0x3eb04c0] VPS 0 does not exist
[hevc # 0x3eb04c0] SPS 0 does not exist.
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'video.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2mp41
encoder : Lavf58.7.100
Duration: 00:00:59.46, start: 0.000000, bitrate: 5894 kb/s
Stream #0:0(und): Video: hevc (Main) (hev1 / 0x31766568), yuv420p(tv, progressive), 3840x2160 [SAR 1:1 DAR 16:9], 5891 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 29.97 tbc (default)
Metadata:
handler_name : VideoHandler
Input #1, png_pipe, from 'logo.png':
Duration: N/A, bitrate: N/A
Stream #1:0: Video: png, rgba(pc), 528x128 [SAR 11339:11339 DAR 33:8], 25 tbr, 25 tbn, 25 tbc
Input #2, mov,mp4,m4a,3gp,3g2,mj2, from 'text.mov':
Metadata:
major_brand : qt
minor_version : 512
compatible_brands: qt
encoder : Lavf57.56.100
Duration: 00:00:06.00, start: 0.000000, bitrate: 1276 kb/s
Stream #2:0(eng): Video: qtrle (rle / 0x20656C72), bgra, 1920x1080, 1274 kb/s, SAR 1:1 DAR 16:9, 25 fps, 25 tbr, 12800 tbn, 12800 tbc (default)
Metadata:
handler_name : DataHandler
Stream mapping:
Stream #0:0 (hevc_cuvid) -> scale_npp
Stream #1:0 (png) -> scale
Stream #2:0 (qtrle) -> scale
fade -> Stream #0:0 (h264_nvenc)
Press [q] to stop, [?] for help
Output #0, mp4, to 'output.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2mp41
encoder : Lavf58.12.100
Stream #0:0: Video: h264 (h264_nvenc) (Main) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], q=-1--1, 2000 kb/s, 29.97 fps, 30k tbn, 29.97 tbc (default)
Metadata:
encoder : Lavc58.18.100 h264_nvenc
Side data:
cpb: bitrate max/min/avg: 0/0/2000000 buffer size: 4000000 vbv_delay: -1
frame= 1783 fps=151 q=30.0 Lsize= 15985kB time=00:00:59.45 bitrate=2202.4kbits/s dup=4 drop=0 speed=5.04x
video:15977kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.050389%
Not sure what to make of this, pretty new to ffmpeg.

Answer 1

See this portion,
Stream #0:0 (hevc_cuvid) -> scale_npp
Stream #1:0 (png) -> scale
Stream #2:0 (qtrle) -> scale
fade -> Stream #0:0 (h264_nvenc)
hevc_cuvid is the decoder for the input stream 0:0 and h264_nvenc is the encoder for the output stream 0:0. Both are hardware accelerated.
The other two input video streams have codecs PNG and QTRLE, for which, no hardware acceleration is available.