Olly, the author of OllyDbg, presents his new open source joke:

PAPERBACK v1.10

Updated by Michael Mohr

Download PaperBack v1.10
Download sources v1.10

PaperBack version 1.00 does not implement AES encryption properly.  Specifically:

a) The key used for (en|de)cryption in version 1.00 provides at most an effective key strength of less than 50 bits (and likely far less, perhaps on the order of 15-25 bits, depending on password quality) instead of the expected 256 bits.  Version 1.10 derives the encryption key from the password via key stretching, significantly improving key strength.  This change causes a small delay in the encryption step.

b) PaperBack version 1.0 implements ECB mode symmetric encryption.  This mode is subject to a watermark attack and leaks information about the encrypted data.  Version 1.00 changes the encryption mode to CBC, which mitigates this attack.

2) AES key length is now selectable in paperbak.h via AESKEYLEN.  I suggest not using AES-256, as its key schedule is known to be substandard.  See Bruce Schneier's website for details.  For the moment I've switched PaperBack to use AES-192.

3) The included libraries are now packaged as binary .lib files.  Instructions for rebuilding them from source are included in README.md from the PaperBack source code.

(Olly: mea maxima culpa. I am no cryptanalytic, and wrote Paperback quickly and without much thinking about the strength of the code. Btw, can this new release read old bitmaps?)


PAPERBACK v1.00

Download PaperBack v1.00
Download sources v1.00
Read GNU GPL


1. What is PaperBack?
2. Installation.
3. Setup.
4. Printing data to paper.
5. Data restoration.
6. History.
7. Patents and IP.
8. Acknowledgements.
9. Source code description.


1. What is PaperBack?

PaperBack is a free application that allows you to back up your precious files on the ordinary paper in the form of the oversized bitmaps. If you have a good laser printer with the 600 dpi resolution, you can save up to 500,000 bytes of uncompressed data on the single A4/Letter sheet. Integrated packer allows for much better data density - up to 3,000,000+ (three megabytes) of C code per page.

You may ask - why? Why, for heaven's sake, do I need to make paper backups, if there are so many alternative possibilities like CD-R's, DVD±R's, memory sticks, flash cards, hard disks, streamer tapes, ZIP drives, network storages, magnetooptical cartridges, and even 8-inch double-sided floppy disks formatted for DEC PDP-11? (I still have some). The answer is simple: you don't. However, by looking on CD or magnetic tape, you are not able to tell whether your data is readable or not. You must insert your medium into the drive (if you have one!) and try to read it.

Paper is different. Do you remember the punched cards? EBCDIC and all this stuff. For years, cards were the main storage medium for the source code. I agree that 100K+ programs were... unhandly, but hey, only real programmers dared to write applications of this size. And used cards were good as notepads, too. Punched tapes were also common. And even the most weird codings, like CDC or EBCDIC, were readable by humans (I mean, by real programmers).

Of course, bitmaps produced by PaperBack are also human-readable (with the small help of any decent microscope). I'm joking. What you need is a scanner attached to PC. Actual version is for Windows only, but it's free and open source, and there is nothing that prevents you from porting PaperBack to Linux or Mac, and the chances are good that it still will work under Windows XXXP or Trillenium Edition. And, of course, you can mail your printouts to the recipients anywhere in the world, even if they have no Internet access or live in the countries where such access is restricted by the regiment.

Oh yes, a scanner. For 600 dpi printer you will need a scanner with at least 900 dpi physical (let me emphasize, physical, not interpolated) resolution.

Have I already mentioned that PaperBack is free? I release it under the GNU General Public License, version 3. This means that you pay nothing for the program, that the sources are freely available, and that you are allowed - in fact, encouraged - to modify and improve this application.


2. Installation.

You don't need to install PaperBack. Copy it to any directory, if possible, with unrestricted write access (to allow PaperBack to save settings to the initialization file), optionally create shortcut on the desktop - that's all.


3. Setup.

This is how Options dialog looks:

Options dialog


The most important setting is the dot density. It determines the size of the data bit on the paper and must be at least two times lower than the physical resolution of your printer. For example, if you are the (moderately) happy owner of the HP LaserJet V with 600 dpi resolution, set density to 300 dpi. This allows you to draw 300x300=90,000 dots, or slightly less than 6 k bytes of useful data on every square inch of the paper.

Jet printers are not as good as laser. Maximal useful resolution is typically limited to 200 dpi. Please select the best available quality, and don't forget to align the printing nozzles, so that points printed from left to right coincide with those printed from right to left.

Dots must be clearly distinguishable from each other. Usually this means that they must be separated by some anount of white space, determined by the parameter dot size. 70% is usually the best option.

Compression is always good, because it reduces the size of the bitmap, unless your file is already packed. Use fast compression if your computer is really, really slow, and maximal compression in all other cases.

Redundancy helps to recover partially damaged data. Redundancy 1:5 means that for every 5 consecutive data blocks, if one block is completely unreadable, PaperBack will be able to restore it. To reduce damages caused by coffee pots and other common dangers, blocks are distributed around the page. Higher redundancy decreases page capacity but improves reliability.

Header and footer asks PaperBack to print useful information about the file, like file name, its size, date of last modification, page and recommended scanner settings. This parameter influences only the printing and has no influence on the reading of the data. Border around the page improves autocropping with the not-so-smart TWAIN drivers.

Large files will be printed on several pages. When last page is scanned (order is not important) and autosave option is activated, PaperBack will ask you to select location where restored file will be saved. If this option is unchecked, you must press Save button when recognition is finished - convenient if your scanner has automatical feeder and you scan several backups (up to 5) at once.

PaperBack uses Highly Sophisticated Unbelievably Advanced Error Correction Techniques (in fact, Reed-Solomon ECC) to restore unreadable pixels. Therefore, if data is halfway readable, it will accept it, even if recognition parameters are very far from optimal. This accelerates processing but leads to the high amount of bad blocks reported by the program. When you backup important data and verify it afterwards, this may lead to false assumption that data is unreliable. But activate Determine best quality, and PaperBack will report the real data quality. Of course, this costs time.

Two last options set data encryption (FIPS-197 compliant AES is not easy to crack) and whether password is displayed as the readable text while you type it in, or the characters are replaced by asterisks. Of course, this option does not mean that password will be printed on the paper!


4. Printing data to paper.

First, set page size and printer options. They may differ from one driver to another, so I will not discuss them here in details. Always select the best available printing quality. Turn off halftoning, dithering and image optimization. Don't forget to align nozzles on jet printers; if possible, turn off bidirectional printing. Note that only basic printer options are saved between the sessions, and you may need to re-enter them again.

After options are set, you can print your data. Current PaperBack version is 1.00, and it can't backup folders - only the single files, at most one per page. This is the very substantial drawback for the backup program. If you are going to save many small files, better first pack them into the single archive using WinZip, tar or similar program.

PaperBack supports drag-and-drop. If file has extention other than .bmp, it will be printed. Default action for bitmaps is the recognition. To  backup them, use Print button. You can drop several files at once; internal queue is limited to 128 entries. Again, each file will be printed on the separate sheet(s) of paper.

For test purposes, you can save bitmaps to the disk. This option is selectable from the main menu.


5. Data restoration.

PaperBack should support any scanner with TWAIN interface. It also accepts uncompressed grayscale and RGB bitmaps with 8 or 24 bits per pixel. You can drag-and-drop files with extention .bmp directly into the PaperBack.

If you use scanner, select scanning source from the main menu, then press Scan button. Optimal resolution is about 3 times the dot density. B/W scans are usually unreadable, always select grayscale image. Color scanning is also acceptable, but has no advantages except for 3-fold memory use. (Another joke). Memory requirements are relatively high. A4 grayscale bitmap with 900 dpi resolution requires around 80 MB.

Turn off all image optimizations, like sharpening - PaperBack uses its own optimization techniques better suitable for this particular case.

Grid should be more or less parallel to the sides of the scanner (maximal angle must not exceed ±7°), but general orientation is unimportant: portrait, landscape, upside down or even, if you use transparencies, flipped. Orientation may change from one paper sheet to another.

You can scan up to 5 backups simultaneously. Each file will be placed into the separate tab. If backup consists of several pages, the order in which they are scanned is absolutely unimportant. Bottom line in the tab displays list of unscanned or incomplete pages. If some page is unreadable, change its placement, resolution and/or brightness and contrast.

Quality map to the right shows distribution of errors on the last scanned page as a gradations of colours. Good blocks are green. The higher the number of erroneous bytes, the more reddish is the colour. Undeciphereble blocks with more than 16 invalid bytes are black. If block is white, PaperBack was unable to recognize the grid. Doubleclick map to display the block as a grayscale image (optionally with marked errors).

After all pages are scanned, press on Save to write restored file to the disk. If backup is encrypted, you will be asked to enter the password.


6. History.

Once upon a time, my oldest son (he was 15 then) asked me: "Dad, how the huge amounts of data are saved on the small CD?" A brief explanation from my side followed, I took a very sharp pencil and tried to draw as small points and lines as possible, in order to emphasize how dense the data is. Then my son asked: "How much data can you place this way on the single sheet of paper?" My estimation was in the order of 100 K. "Can we make a try?" It took me four or five days to make the proof of concept, and another two weeks to integrate packer, encryption and user interface. Then I lost the interest and put the whole project into the darkest corner of the deepest directory on my hard disk. (One more joke). But why keep potentially useful code to myself? So now I am releasing it under GPL 3.


7. Patents and IP.

PaperBack is a "clean-room" implementation. I assure that my part of code is written by myself alone and is not based on any 3-rd party work.

However, I can't guarantee that this program doesn't infringe any patents, trade marks or other stuff that makes lawyers rich. If you are going to use PaperBack, all the burden of proof is on your side.

To make lawyers (un)happy:

Calculo B - Diva Flemming 6 Edicao Pdf |verified| May 2026

Mastering Multivariable Math: A Deep Dive into Cálculo B (6th Edition)

For many students in engineering, physics, and mathematics, the transition from single-variable calculus to the multivariable world is a rite of passage. At the heart of this transition in many Brazilian universities is Cálculo B

by Diva Marília Flemming and Mírian Buss Gonçalves. The 6th edition, often sought as a digital PDF for study convenience, remains a gold standard for its pedagogical clarity and comprehensive scope. Why This Edition Matters

The 6th edition is more than just a minor update; it is a "modernized" approach that consolidated content previously found across multiple volumes (specifically the former Cálculo C) into a single, functional source. It is designed to bridge the gap between abstract theory and practical application, serving both the humanities (like Economics) and the exact sciences (Engineering and Physics). Core Pillars of the 6th Edition

The text is structured to guide you through the complexities of spatial mathematics: Functions of Several Variables: Moving beyond the plane into

-dimensional spaces. It begins with the fundamental definitions and visual interpretations of these functions.

Multiple Integrals: Mastering double and triple integrals is essential for calculating volumes and masses of complex shapes.

Vector Calculus: The 6th edition provides a robust framework for line (curvilinear) and surface integrals, which are the backbone of electromagnetism and fluid dynamics.

Practical Problem Solving: One of the hallmarks of Flemming’s work is the abundance of exercises—over 1,500 in the series—often accompanied by step-by-step resolution guides. The Pedagogical Edge

What sets Diva Flemming's work apart is its "didactic and dynamic" exposition. The authors prioritize visual mathematics, using illustrations to help students mentally visualize surfaces and vector fields. This shift from mechanical rule-following to conceptual understanding is critical for developing the problem-solving skills required in modern professional fields. Digital Study and Resources

The demand for the "6th Edition PDF" highlights a shift toward digital-first learning. Students often supplement the textbook with: Diva Flemming - Cálculo B | PDF - Scribd

Para estudantes de engenharia, matemática e física, o livro Cálculo B, de Diva Marília Flemming e Mirian Buss Gonçalves, é uma ferramenta indispensável. Diferente de outros manuais técnicos, a obra é amplamente reconhecida por sua didática clara, que equilibra o rigor teórico com a aplicação prática imediata.

Embora o termo "6ª edição" seja frequentemente associado ao volume anterior (Cálculo A, focado em funções de uma variável), o Cálculo B é consolidado em sua 2ª edição revisada e ampliada como o volume que trata de funções de várias variáveis. O que você encontrará no Cálculo B

O livro aprofunda o estudo iniciado no primeiro volume, focando em conceitos fundamentais para o cálculo multivariável e vetorial: Amazon.com: Cálculo B (Em Portuguese do Brasil)

Cálculo B, written by Diva Marília Flemming and Mirian Buss Gonçalves, is a cornerstone textbook for multivariate and vector calculus. While the 6th edition is widely recognized for the series' first volume (Cálculo A), Cálculo B is most commonly utilized in its 2nd edition (published by Pearson/Prentice Hall), which was significantly expanded to include content from the authors' previous Cálculo C. Core Content and Structure

The book is designed for students in mathematics, physics, chemistry, and engineering, focusing on clarity and practical application. It typically covers: calculo b - diva flemming 6 edicao pdf

I can’t help find or provide pirated copies of copyrighted books. If you’d like, I can:

Which option do you want?

"Cálculo B: Funções de várias variáveis, integrais múltiplas, integrais curvilíneas e de superfície" by Diva Marília Flemming and Mirian Buss Gonçalves is a core resource for multivariate calculus in Brazil. The text covers advanced calculus topics, including partial derivatives, multiple integrals, and vector calculus. Access a full-text version of the book at the Internet Archive. Exer Calculo B - Diva Flemming.pdf - TsXVPSBR!

Mastering Multivariable Mathematics with Cálculo B: Diva Flemming's Definitive Guide

For students in engineering, physics, and mathematics, the transition from single-variable calculus to the multivariable world is a major milestone. Cálculo B

by Diva Marília Flemming and Mírian Buss Gonçalves is widely considered one of the most effective tools for making this jump. The 6th Edition

(often sought as a PDF for digital study) continues the authors' legacy of balancing rigorous theory with practical, clear-cut applications. Why Cálculo B is an Essential Resource

Unlike more abstract textbooks, Flemming and Gonçalves focus on didactic clarity

. They understand that multivariable concepts—like visualizing a function in 3D or calculating flow through a surface—can be daunting. The 6th Edition

was specifically revised to include more illustrations and practical applications, making the abstract tangible for students Key Topics Covered in the 6th Edition

The textbook is structured to guide you through the complexities of multivariable calculus systematically. Here are the core pillars: Functions of Several Variables : Transitioning from

. This section covers domains, limits, and continuity in higher dimensions. Partial Derivatives & Gradients

: Understanding how a function changes along different axes. This includes the chain rule for multivariable functions and directional derivatives. Multiple Integrals

: Learning to calculate volumes and masses using double and triple integrals. Vector Calculus

: This is where "Cálculo B" shines, covering line and surface integrals, along with essential theorems like Green's, Stokes', and the Divergence (Gauss) Theorem. Differential Equations (EDOs) Mastering Multivariable Math: A Deep Dive into Cálculo

: Introducing techniques to solve second-order equations and initial value problems. Responde Aí What’s New in the Recent Editions? The 6th Edition of "Cálculo A" and subsequent updates to Cálculo B

consolidated a lot of material. Notably, recent versions now include content previously found in "Cálculo C," such as advanced vector functions, making it a more comprehensive "one-stop" source for undergraduate students. Study Tips for Success If you are using the Cálculo B PDF to study, keep these tips in mind: Solve the Examples

: Don't just read them. The book is famous for its step-by-step examples. Re-calculate them before attempting the end-of-chapter exercises. Use External Solvers : Platforms like Responde Aí

offer step-by-step solutions specifically for Diva Flemming’s exercises, which is invaluable when you get stuck on a complex triple integral. Focus on Visuals

: Pay attention to the 3D graphs. Understanding the geometry of surfaces is 50% of the battle in multivariable calculus. Responde Aí Cálculo B

remains a cornerstone of Brazilian technical education because it doesn't just teach you how to compute; it teaches you how to think in three dimensions. or help with a particular exercise type from the book? Cálculo B - Diva Flemming | PDF - Scribd

O livro Cálculo B: Funções de várias variáveis, integrais múltiplas, integrais de linha e de superfície, escrito por Diva Marília Flemming e Miriam Buss Gonçalves, é uma das obras mais respeitadas no ensino superior brasileiro. Chegando à sua 6ª edição, o material se consolidou como o "braço direito" de estudantes de Engenharia, Física, Matemática e Química.

Se você está buscando informações sobre o conteúdo, a importância desta edição ou como utilizar o material em seus estudos, este guia detalha tudo o que você precisa saber. O que há de novo na 6ª Edição?

A 6ª edição de Cálculo B não é apenas uma republicação. As autoras trabalharam para tornar a linguagem ainda mais acessível, mantendo o rigor matemático necessário para as disciplinas de Cálculo II e III.

Revisão de Exercícios: Centenas de problemas foram revisados para garantir clareza e precisão.

Layout Modernizado: O projeto gráfico facilita a leitura de fórmulas complexas e a visualização de gráficos tridimensionais.

Exemplos Práticos: Maior foco em aplicações reais, conectando a teoria matemática com problemas práticos da engenharia. Principais Tópicos Abordados

O livro é estruturado de forma lógica, partindo da extensão do Cálculo A (uma variável) para o ambiente multidimensional. 1. Funções de Várias Variáveis Estudo de domínio, curvas de nível e limites no espaço Rncap R to the n-th power . É a base para entender como superfícies se comportam. 2. Derivadas Parciais e Diferenciabilidade

Introdução ao vetor gradiente, regra da cadeia para várias variáveis e otimização (máximos e mínimos), incluindo os multiplicadores de Lagrange. 3. Integrais Múltiplas

Cálculo de áreas e volumes através de integrais duplas e triplas. O livro destaca-se pelas explicações detalhadas sobre mudança de variáveis (coordenadas polares, cilíndricas e esféricas). 4. Cálculo Vetorial Help locate legal sources (publisher page, library, or

Um dos pontos fortes da obra. Aborda campos vetoriais, integrais de linha e de superfície, culminando nos Teoremas de Green, Stokes e Gauss (Divergência). Por que o "Diva Flemming" é tão popular?

Diferente de livros estrangeiros traduzidos, que às vezes possuem uma linguagem truncada, a obra de Flemming e Gonçalves foi escrita pensando no currículo das universidades brasileiras.

Didática Progressiva: O conteúdo começa de forma simples e aumenta a complexidade gradualmente.

Respostas e Soluções: Quase todos os exercícios propostos possuem respostas ao final do livro, o que facilita o autodidatismo.

Foco no Passo a Passo: As autoras não "pulam etapas" nos exemplos resolvidos, o que reduz a frustração do aluno. Como estudar pelo Cálculo B de forma eficiente?

Não ignore os gráficos: No Cálculo B, a visualização espacial é tudo. Tente desenhar as regiões de integração antes de montar a conta.

Faça os exercícios ímpares primeiro: Geralmente, eles seguem a lógica dos exemplos resolvidos no capítulo.

Use ferramentas de apoio: Ao estudar por PDF ou livro físico, complemente a visualização de superfícies com softwares como o GeoGebra. Onde encontrar o material?

Embora muitos estudantes busquem pela versão em PDF da 6ª edição por facilidade de transporte, vale lembrar que o livro físico é um excelente investimento para consulta rápida durante a graduação. Ele está disponível nas principais livrarias e bibliotecas universitárias do país.

Para quem utiliza a versão digital, certifique-se de procurar por edições que mantenham a integridade das fórmulas, pois versões digitalizadas de baixa qualidade podem omitir sinais matemáticos importantes.

Você gostaria de uma lista de exercícios resolvidos sobre algum tópico específico do livro, como Integrais Triplas ou Teorema de Stokes?

It looks like you’re looking for a deep feature (likely a table of contents, index, solved problems, or specific section) from the book "Cálculo B" – Diva Flemming, 6th edition in PDF format.

However, I’m not able to directly provide or link to copyrighted PDFs. What I can do is help you find what to look for inside the PDF once you have legitimate access to it (e.g., through an institutional library, purchased ebook, or instructor’s materials).

Here are the deep features you might want to search for inside the PDF:

Option B (Low Cost)

Step 3: Use the Solved Examples

The 6th edition has over 150 "Exemplos" in the margins. Do not just read them – cover the solution with a piece of paper and attempt to solve them yourself first.

How to Study with "Calculo B - Diva Flemming 6 Edicao PDF"

Possessing the PDF is only half the battle. Here is a proven study method using this specific textbook.



8. Acknowledgements.

PaperBack would be not possible without the Reed-Solomon error correction. The code is written by Phil Karn (C) 2002. Phil allows use of his code under the terms of GPL.

AES encryption code is developed by Christophe Devine (C) 2001-2004. This code is also released under GPL.

bzip2 compression engine is developed by Julian R. Seward (C) 1996-2005. See sources for details. To my best knowledge (IANAL), his license is compatible with GPL.


9. Source code description.

There is currently none, but the sources are commented. If you need help, read comments. If you still need help, ask your friends. For more help, visit some discussion forum. If you are completely despaired, create your own forum. If you are ready to commit suicide, well, drop me a mail (ollydbg at t-online de). Set subject to PaperBack, or you will be considered spam and filtered out. Allow 4 to 6 weeks for delivery.


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