AZW3 won't convert

[bartveld]

For the first time ever I have an AZW3-file that will not convert to epub in Calibre. The job is stuck on 1% now for about 10 minutes. As I've always blindly relied on Calibre's ability to convert I'm in the dark as to what may be happening here.

Spoiler:

Convert book 1 of 1 (One Hundred Days: Napoleon's Road to Waterloo)
Conversion options changed from defaults:
cover: u'C:\\Users\\Veld\\AppData\\Local\\Temp\\calibre_8 optd2\\fli0w7.jpeg'
enable_heuristics: True
verbose: 2
italicize_common_cases: False
filter_css: u'margin-left,margin,margin-right,margin-top,,margin-bottom'
read_metadata_from_opf: u'C:\\Users\\Veld\\AppData\\Local\\Temp\\calibre_8 optd2\\de6wbg.opf'
output_profile: 'kindle'
extra_css: u'p\n{\nmargin:5pt;\nwidows: 1;\norphans: 1;\n}'
Resolved conversion options
calibre version: 3.10.0
{'asciiize': False,
'author_sort': None,
'authors': None,
'base_font_size': 0.0,
'book_producer': None,
'change_justification': u'original',
'chapter': u"//*[((name()='h1' or name()='h2') and re:test(., '\\s*((chapter|book|section|part)\\s+)|((prolog|pr ologue|epilogue)(\\s+|$))', 'i')) or @class = 'chapter']",
'chapter_mark': u'pagebreak',
'comments': None,
'cover': u'C:\\Users\\Veld\\AppData\\Local\\Temp\\calibre_8 optd2\\fli0w7.jpeg',
'debug_pipeline': None,
'dehyphenate': True,
'delete_blank_paragraphs': True,
'disable_font_rescaling': False,
'dont_split_on_page_breaks': False,
'duplicate_links_in_toc': False,
'embed_all_fonts': False,
'embed_font_family': None,
'enable_heuristics': True,
'epub_flatten': False,
'epub_inline_toc': False,
'epub_toc_at_end': False,
'expand_css': False,
'extra_css': u'p\n{\nmargin:5pt;\nwidows: 1;\norphans: 1;\n}',
'extract_to': None,
'filter_css': u'margin-left,margin,margin-right,margin-top,,margin-bottom',
'fix_indents': True,
'flow_size': 260,
'font_size_mapping': None,
'format_scene_breaks': True,
'html_unwrap_factor': 0.4,
'input_encoding': None,
'input_profile': <calibre.customize.profiles.InputProfile object at 0x054C3070>,
'insert_blank_line': False,
'insert_blank_line_size': 0.5,
'insert_metadata': False,
'isbn': None,
'italicize_common_cases': False,
'keep_ligatures': False,
'language': None,
'level1_toc': None,
'level2_toc': None,
'level3_toc': None,
'line_height': 0.0,
'linearize_tables': False,
'margin_bottom': 5.0,
'margin_left': 5.0,
'margin_right': 5.0,
'margin_top': 5.0,
'markup_chapter_headings': True,
'max_toc_links': 50,
'minimum_line_height': 120.0,
'no_chapters_in_toc': False,
'no_default_epub_cover': False,
'no_inline_navbars': False,
'no_svg_cover': False,
'output_profile': <calibre.customize.profiles.KindleOutput object at 0x054C33D0>,
'page_breaks_before': u"//*[name()='h1' or name()='h2']",
'prefer_metadata_cover': False,
'preserve_cover_aspect_ratio': False,
'pretty_print': True,
'pubdate': None,
'publisher': None,
'rating': None,
'read_metadata_from_opf': u'C:\\Users\\Veld\\AppData\\Local\\Temp\\calibre_8 optd2\\de6wbg.opf',
'remove_fake_margins': True,
'remove_first_image': False,
'remove_paragraph_spacing': False,
'remove_paragraph_spacing_indent_size': 1.5,
'renumber_headings': True,
'replace_scene_breaks': u'',
'search_replace': '[]',
'series': None,
'series_index': None,
'smarten_punctuation': False,
'sr1_replace': None,
'sr1_search': None,
'sr2_replace': None,
'sr2_search': None,
'sr3_replace': None,
'sr3_search': None,
'start_reading_at': None,
'subset_embedded_fonts': False,
'tags': None,
'timestamp': None,
'title': None,
'title_sort': None,
'toc_filter': None,
'toc_threshold': 6,
'toc_title': None,
'transform_css_rules': '[]',
'unsmarten_punctuation': False,
'unwrap_lines': True,
'use_auto_toc': False,
'verbose': 2}
InputFormatPlugin: MOBI Input running
on C:\Users\Veld\AppData\Local\Temp\calibre_8optd2\dp fest.azw3
Found KF8 MOBI of type 'standalone'
Extracting text...
Parsing all content...
Parsing styles/0001.css ...
Parsing text/part0000.html ...
********* Heuristic processing HTML *********
There are 95 blank lines. 0.0340868317187 percent blank
minimum chapters required are: 23
found 0 pre-existing headings
numeric_title had 12 hits - 10 chapters with no title, 2 chapters with titles, 0.166666666667 percent.

[kovidgoyal]

Just let it run. From that log you have turned onheuristic processing, which is slow.

[bartveld]

Well, I've let it run for 1 hour and 40 minutes and it's still at 1 percent. There's nothing unusual about this 0.7 Mb file (actually it's this one, from today's non-fiction freebies on this forum). Books like that usually take a minute max to convert.
It's not a biggie, I'm just surprised.

[Brett Merkey]

@ bartveld,
Thanks for the tip on the book. It is one I want to read. I downloaded it, and converted to epub without problems. Looking at the code, I don't see any of the troublesome issues that may cause Calibre to choke except this: the stylesheet is practically empty. EVERY paragraph has its style inline. I suppose this could take some computer configurations a long while to parse...

[bartveld]

Glad I could give you the pointer! Do you ever visit this thread? You may find more...

Did you convert in Calibre? If so, how long did it take?

[JSWolf]

Stop the conversion. There's a much better and much faster way to do this.

Install the KindleUnpack plugin and use it to shift the KF8 code to ePub. Then use epubcheck to validate the ePub and fix any errors and once that's done with no errors, you are good to go.

[bartveld]

Originally Posted by JSWolf

Stop the conversion. There's a much better and much faster way to do this.

Install the KindleUnpack plugin and use it to shift the KF8 code to ePub. Then use epubcheck to validate the ePub and fix any errors and once that's done with no errors, you are good to go.

Good suggestion, JSWolf! I'd never even heard of that plugin, but it works like a charm. Thanks!

[JSWolf]

Originally Posted by bartveld

Good suggestion, JSWolf! I'd never even heard of that plugin, but it works like a charm. Thanks!

Happy to help.

[gbm]

Originally Posted by bartveld

Glad I could give you the pointer! Do you ever visit this thread? You may find more...

Did you convert in Calibre? If so, how long did it take?

I converted it using both my window tablet* and my 10 year old desktop Linux PC. The tablet took 1 minute and 48 seconds the desktop took 41 seconds.

*Quad core Atom processor and 1gb of memory 32 bit windows10.

bernie

[JSWolf]

Originally Posted by gbm

I converted it using both my window tablet* and my 10 year old desktop Linux PC. The tablet took 1 minute and 48 seconds the desktop took 41 seconds.

*Quad core Atom processor and 1gb of memory 32 bit windows10.

bernie

Do you turn on heuristic processing? The OP had that turned on.

[kovidgoyal]

Originally Posted by bartveld

Well, I've let it run for 1 hour and 40 minutes and it's still at 1 percent. There's nothing unusual about this 0.7 Mb file (actually it's this one, from today's non-fiction freebies on this forum). Books like that usually take a minute max to convert.
It's not a biggie, I'm just surprised.

Just turn off heuristic processing.

[theducks]

Originally Posted by gbm

I converted it using both my window tablet* and my 10 year old desktop Linux PC. The tablet took 1 minute and 48 seconds the desktop took 41 seconds.

*Quad core Atom processor and 1gb of memory 32 bit windows10.

bernie

Calibre does not divide a task between cores. I am not even sure that a second conversion will land on another core.

[JSWolf]

Originally Posted by theducks

Calibre does not divide a task between cores. I am not even sure that a second conversion will land on another core.

Actually, Calibre can use multiple cores for conversions. The settings for this are in Preferences > Miscellaneous

[kovidgoyal]

Originally Posted by theducks

Calibre does not divide a task between cores. I am not even sure that a second conversion will land on another core.

It most definitely does. Every conversion is an independent process and uses a separate core.

[DoctorOhh]

Originally Posted by bartveld

Glad I could give you the pointer! Do you ever visit this thread? You may find more...

Did you convert in Calibre? If so, how long did it take?

I'm glad JSWolf was able to point you to a solution.

Another obvious solution is to not have heuristic processing turned on by default. Save heuristic processing only for the rare books that exhibit some sort of issue you need help correcting.

This book took all of 19 seconds to convert flawlessly to epub.