Was working on mainly on 2 different pcs (ubuntu 16.04 and ubuntu 18.04). Output of pdflatex was the same for both.
When compiling the exact same file on a different laptop (freshly installed with ubuntu 19.04, texlive-full, and kile), many of the figures shrank.
Painstakingly fixed all the shrank figures, just to realize later that compiling the file on the pc they were all huge now.
Edit - The following is a minimized version of the code (which exhibits the problem):
\documentclass{report}
\usepackage{subcaption}
\usepackage{graphicx}
\begin{document}
\begin{figure}[t]%[h!]
\centering
\subcaptionbox{\label{fig:sample1}}[0.49\linewidth]{\includegraphics[width=0.9\linewidth,trim=0 1cm 0 .5cm, clip]{example-image-a.png}}
\subcaptionbox{\label{fig:sample2}}[0.49\linewidth]{\includegraphics[width=0.9\linewidth,trim=0 1cm 0 .5cm, clip]{example-image-a.png}}
\caption{sample text}
\label{fig:sample3}
\end{figure}
\end{document}
Compiling this on the pc results with:
Compiling on the laptop results with:
PC Log:
This is pdfTeX, Version 3.14159265-2.6-1.40.16 (TeX Live 2015/Debian) (preloaded format=pdflatex)
restricted \write18 enabled.
entering extended mode
(./thesis.tex
LaTeX2e <2016/02/01>
Babel <3.9q> and hyphenation patterns for 81 language(s) loaded.
(/usr/share/texlive/texmf-dist/tex/latex/base/report.cls
Document Class: report 2014/09/29 v1.4h Standard LaTeX document class
(/usr/share/texlive/texmf-dist/tex/latex/base/size10.clo))
(/usr/share/texlive/texmf-dist/tex/latex/caption/subcaption.sty
(/usr/share/texlive/texmf-dist/tex/latex/caption/caption.sty
(/usr/share/texlive/texmf-dist/tex/latex/caption/caption3.sty
(/usr/share/texlive/texmf-dist/tex/latex/graphics/keyval.sty))))
(/usr/share/texlive/texmf-dist/tex/latex/graphics/graphicx.sty
(/usr/share/texlive/texmf-dist/tex/latex/graphics/graphics.sty
(/usr/share/texlive/texmf-dist/tex/latex/graphics/trig.sty)
(/usr/share/texlive/texmf-dist/tex/latex/latexconfig/graphics.cfg)
(/usr/share/texlive/texmf-dist/tex/latex/pdftex-def/pdftex.def
(/usr/share/texlive/texmf-dist/tex/generic/oberdiek/infwarerr.sty)
(/usr/share/texlive/texmf-dist/tex/generic/oberdiek/ltxcmds.sty))))
(./thesis.aux) (/usr/share/texlive/texmf-dist/tex/context/base/supp-pdf.mkii
[Loading MPS to PDF converter (version 2006.09.02).]
) (/usr/share/texlive/texmf-dist/tex/generic/oberdiek/pdftexcmds.sty
(/usr/share/texlive/texmf-dist/tex/generic/oberdiek/ifluatex.sty)
(/usr/share/texlive/texmf-dist/tex/generic/oberdiek/ifpdf.sty))
(/usr/share/texlive/texmf-dist/tex/latex/oberdiek/epstopdf-base.sty
(/usr/share/texlive/texmf-dist/tex/latex/oberdiek/grfext.sty
(/usr/share/texlive/texmf-dist/tex/generic/oberdiek/kvdefinekeys.sty))
(/usr/share/texlive/texmf-dist/tex/latex/oberdiek/kvoptions.sty
(/usr/share/texlive/texmf-dist/tex/generic/oberdiek/kvsetkeys.sty
(/usr/share/texlive/texmf-dist/tex/generic/oberdiek/etexcmds.sty)))
(/usr/share/texlive/texmf-dist/tex/latex/latexconfig/epstopdf-sys.cfg))
<example-image-a.png, id=1, 401.5pt x 301.125pt> <use example-image-a.png>
Overfull \hbox (141.446pt too wide) in paragraph at lines 7--7
[][]
<use example-image-a.png>
Overfull \hbox (141.446pt too wide) in paragraph at lines 8--8
[][]
[1{/var/lib/texmf/fonts/map/pdftex/updmap/pdftex.map} </usr/share/texlive/texmf
-dist/tex/latex/mwe/example-image-a.png>] (./thesis.aux) )
(see the transcript file for additional information)</usr/share/texlive/texmf-d
ist/fonts/type1/public/amsfonts/cm/cmr10.pfb></usr/share/texlive/texmf-dist/fon
ts/type1/public/amsfonts/cm/cmr9.pfb>
Output written on thesis.pdf (1 page, 25985 bytes).
Transcript written on thesis.log.
PC File list:
*File List*
report.cls 2014/09/29 v1.4h Standard LaTeX document class
size10.clo 2014/09/29 v1.4h Standard LaTeX file (size option)
subcaption.sty 2016/02/20 v1.1-142 Sub-captions (AR)
caption.sty 2016/02/21 v3.3-144 Customizing captions (AR)
caption3.sty 2016/02/04 v1.7-139 caption3 kernel (AR)
keyval.sty 2014/10/28 v1.15 key=value parser (DPC)
graphicx.sty 2014/10/28 v1.0g Enhanced LaTeX Graphics (DPC,SPQR)
graphics.sty 2016/01/03 v1.0q Standard LaTeX Graphics (DPC,SPQR)
trig.sty 2016/01/03 v1.10 sin cos tan (DPC)
graphics.cfg 2010/04/23 v1.9 graphics configuration of TeX Live
pdftex.def 2011/05/27 v0.06d Graphics/color for pdfTeX
infwarerr.sty 2010/04/08 v1.3 Providing info/warning/error messages (HO)
ltxcmds.sty 2011/11/09 v1.22 LaTeX kernel commands for general use (HO)
supp-pdf.mkii
pdftexcmds.sty 2011/11/29 v0.20 Utility functions of pdfTeX for LuaTeX (HO)
ifluatex.sty 2010/03/01 v1.3 Provides the ifluatex switch (HO)
ifpdf.sty 2011/01/30 v2.3 Provides the ifpdf switch (HO)
epstopdf-base.sty 2010/02/09 v2.5 Base part for package epstopdf
grfext.sty 2010/08/19 v1.1 Manage graphics extensions (HO)
kvdefinekeys.sty 2011/04/07 v1.3 Define keys (HO)
kvoptions.sty 2011/06/30 v3.11 Key value format for package options (HO)
kvsetkeys.sty 2012/04/25 v1.16 Key value parser (HO)
etexcmds.sty 2011/02/16 v1.5 Avoid name clashes with e-TeX commands (HO)
epstopdf-sys.cfg 2010/07/13 v1.3 Configuration of (r)epstopdf for TeX Live
example-image-a.png Graphic file (type png)
example-image-a.png Graphic file (type png)
***********
Laptop log:
This is pdfTeX, Version 3.14159265-2.6-1.40.20 (TeX Live 2019/Debian) (preloaded format=pdflatex)
restricted \write18 enabled.
entering extended mode
(./thesis.tex
LaTeX2e <2018-12-01>
(/usr/share/texlive/texmf-dist/tex/latex/base/report.cls
Document Class: report 2018/09/03 v1.4i Standard LaTeX document class
(/usr/share/texlive/texmf-dist/tex/latex/base/size10.clo))
(/usr/share/texlive/texmf-dist/tex/latex/caption/subcaption.sty
(/usr/share/texlive/texmf-dist/tex/latex/caption/caption.sty
(/usr/share/texlive/texmf-dist/tex/latex/caption/caption3.sty
(/usr/share/texlive/texmf-dist/tex/latex/graphics/keyval.sty))))
(/usr/share/texlive/texmf-dist/tex/latex/graphics/graphicx.sty
(/usr/share/texlive/texmf-dist/tex/latex/graphics/graphics.sty
(/usr/share/texlive/texmf-dist/tex/latex/graphics/trig.sty)
(/usr/share/texlive/texmf-dist/tex/latex/graphics-cfg/graphics.cfg)
(/usr/share/texlive/texmf-dist/tex/latex/graphics-def/pdftex.def)))
(./thesis.aux)
(/usr/share/texlive/texmf-dist/tex/context/base/mkii/supp-pdf.mkii
[Loading MPS to PDF converter (version 2006.09.02).]
) (/usr/share/texlive/texmf-dist/tex/latex/oberdiek/epstopdf-base.sty
(/usr/share/texlive/texmf-dist/tex/generic/oberdiek/infwarerr.sty)
(/usr/share/texlive/texmf-dist/tex/latex/oberdiek/grfext.sty
(/usr/share/texlive/texmf-dist/tex/generic/oberdiek/kvdefinekeys.sty
(/usr/share/texlive/texmf-dist/tex/generic/oberdiek/ltxcmds.sty)))
(/usr/share/texlive/texmf-dist/tex/latex/oberdiek/kvoptions.sty
(/usr/share/texlive/texmf-dist/tex/generic/oberdiek/kvsetkeys.sty
(/usr/share/texlive/texmf-dist/tex/generic/oberdiek/etexcmds.sty
(/usr/share/texlive/texmf-dist/tex/generic/oberdiek/ifluatex.sty))))
(/usr/share/texlive/texmf-dist/tex/generic/oberdiek/pdftexcmds.sty
(/usr/share/texlive/texmf-dist/tex/generic/oberdiek/ifpdf.sty))
(/usr/share/texlive/texmf-dist/tex/latex/latexconfig/epstopdf-sys.cfg))
[1{/var/lib/texmf/fonts/map/pdftex/updmap/pdftex.map} </usr/share/texlive/texmf
-dist/tex/latex/mwe/example-image-a.png>] (./thesis.aux) )</usr/share/texlive/t
exmf-dist/fonts/type1/public/amsfonts/cm/cmr10.pfb></usr/share/texlive/texmf-di
st/fonts/type1/public/amsfonts/cm/cmr9.pfb>
Output written on thesis.pdf (1 page, 25967 bytes).
Transcript written on thesis.log.
Laptop file list:
*File List*
report.cls 2018/09/03 v1.4i Standard LaTeX document class
size10.clo 2018/09/03 v1.4i Standard LaTeX file (size option)
subcaption.sty 2018/05/01 v1.1-162 Sub-captions (AR)
caption.sty 2018/10/06 v3.3-154 Customizing captions (AR)
caption3.sty 2018/09/12 v1.8c caption3 kernel (AR)
keyval.sty 2014/10/28 v1.15 key=value parser (DPC)
graphicx.sty 2017/06/01 v1.1a Enhanced LaTeX Graphics (DPC,SPQR)
graphics.sty 2017/06/25 v1.2c Standard LaTeX Graphics (DPC,SPQR)
trig.sty 2016/01/03 v1.10 sin cos tan (DPC)
graphics.cfg 2016/06/04 v1.11 sample graphics configuration
pdftex.def 2018/01/08 v1.0l Graphics/color driver for pdftex
supp-pdf.mkii
epstopdf-base.sty 2016/05/15 v2.6 Base part for package epstopdf
infwarerr.sty 2016/05/16 v1.4 Providing info/warning/error messages (HO)
grfext.sty 2016/05/16 v1.2 Manage graphics extensions (HO)
kvdefinekeys.sty 2016/05/16 v1.4 Define keys (HO)
ltxcmds.sty 2016/05/16 v1.23 LaTeX kernel commands for general use (HO)
kvoptions.sty 2016/05/16 v3.12 Key value format for package options (HO)
kvsetkeys.sty 2016/05/16 v1.17 Key value parser (HO)
etexcmds.sty 2016/05/16 v1.6 Avoid name clashes with e-TeX commands (HO)
ifluatex.sty 2016/05/16 v1.4 Provides the ifluatex switch (HO)
pdftexcmds.sty 2018/09/10 v0.29 Utility functions of pdfTeX for LuaTeX (HO)
ifpdf.sty 2018/09/07 v3.3 Provides the ifpdf switch
epstopdf-sys.cfg 2010/07/13 v1.3 Configuration of (r)epstopdf for TeX Live
example-image-a.png Graphic file (type png)
example-image-a.png Graphic file (type png)
***********
Any insight would be appreciated.
\listfilesto your preamble and compare the list of package versions that will be printed to the log file on the two machines.