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Very Deep Learning since 1991 - Fast & Deep / Recurrent Neural Networks - Official Site. By Juergen Schmidhuber. Includes adapted HAL 9000 image from Kubrick's movie based on CLarke's Novel: 2001. Also includes images from the German Traffic Sign Recognition Benchmark.
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Deep Learning since 1991: First Very Deep Learners to Win Official Contests in Pattern Recognition, Object Detection, Image Segmentation, Sequence Learning, Through Fast & Deep / Recurrent Neural Networks. Jürgen Schmidhuber, 2009-2014 (compare 2012 interview on KurzweilAI and G+ posts on Deep Learning)

Deep Learning in Artificial Neural Networks (NNs) is about credit assignment across many (not just a few) subsequent computational stages or layers, in deep or recurrent NNs.

The first Deep Learning systems of the feedforward multilayer perceptron type were created half a century ago (Ivakhnenko et al., 1965, 1967, 1968, 1971). The 1971 paper already described an adaptive deep network with 8 layers of neurons. (Our first recurrent Deep Learners were published much later, in 1991 - more below.)

Recently the field has experienced a resurgence. Since 2009, our Deep Learning team has won 9 (nine) first prizes in important and highly competitive international pattern recognition competitions (with secret test set known only to the organisers), far more than any other team. Our neural nets also were the first Very Deep Learners to win such contests (e.g., on classification, object detection, segmentation), and the first machine learning methods to reach superhuman performance in such a contest. Here the list of won competitions (details in the rightmost column):

9. MICCAI 2013 Grand Challenge on Mitosis Detection
8. ICPR 2012 Contest on Mitosis Detection in Breast Cancer Histological Images
7. ISBI 2012 Brain Image Segmentation Challenge (with superhuman pixel error rate)
6. IJCNN 2011 Traffic Sign Recognition Competition (only our method achieved superhuman results)
5. ICDAR 2011 offline Chinese Handwriting Competition
4. Online German Traffic Sign Recognition Contest
3. ICDAR 2009 Arabic Connected Handwriting Competition
2. ICDAR 2009 Handwritten Farsi/Arabic Character Recognition Competition
1. ICDAR 2009 French Connected Handwriting Competition. Compare the overview page on handwriting recognition.

Our Deep Learning methods also set records in important Machine Learning (ML) benchmarks (details again in the rightmost column):

D. Chinese characters from the ICDAR 2013 competition (3755 classes)
C. The MNIST Handwritten Digits Benchmark (perhaps the most famous ML benchmark; we achieved the 1st human-competitive result in 2011)
B. The CIFAR Image Classification Benchmark
A. The NORB Stereo Vision Object Recognition Benchmark

Remarkably, none of 1-9 & A-D above required the traditional sophisticated computer vision techniques developed over the past six decades or so. Instead, our biologically rather plausible systems are inspired by human brains, and learn to recognize objects from numerous training examples. We use deep, artificial, supervised, feedforward or recurrent (deep by nature) neural networks with many non-linear processing stages.

We started work on Very Deep Learning a quarter-century ago. Back then, Sepp Hochreiter (now professor) was an undergrad student working on Schmidhuber's neural net project. His 1991 thesis [2b] is a Deep Learning milestone: it formally showed that deep networks like the above are hard to train because they suffer from the now famous problem of vanishing or exploding gradients. Since then we have developed various techniques to overcome this obstacle (more here). The first system of 1991 used a stack of recurrent neural networks (RNNs) pre-trained in unsupervised fashion [2a,2c] to compactly encode input sequences, where lower layers of the hierarchy learn to extract compact sequence representations fed to higher layers. This can greatly accelerate subsequent supervised learning [2a,2c]. See [2c] for an experiment with 1200 nonlinear virtual layers. The 1991 system also was the first Neural Hierarchical Temporal Memory.

Today's computers are over a million times faster than those of 1991. We also use graphics cards or GPUs (mini-supercomputers for video games, see picture in 2nd column) to speed up learning on standard CPUs by a factor of up to 50. In 2010, we broke the MNIST (benchmark C) record through GPU-based plain backprop for standard NNs (no unsupervised pre-training, no convolution etc) [6]. Our committees of networks improve the results even further [9-13,17-19].

Pattern recognition through Deep Learning is becoming important for thousands of practical applications. For example, the future of search engines lies in image and video recognition as opposed to traditional text search. Autonomous robots such as driverless cars can greatly profit from it, too (see competitions 4,6). Deep Learning may even have lifesaving impact through medical applications such as cancer detection, perhaps the most important application area, with the highest potential impact (see competitions 8,9). Reference [14] uses fast deep nets to achieve superior hand gesture recognition. Reference [16] uses them to achieve superior steel defect detection, three times better than support vector machines (SVM) trained on commonly used feature descriptors.

Note that the successes 1-9 & A-D above did NOT require any unsupervised pre-training, which is a bit depressing, as we have developed unsupervised learning algorithms for 20 years. However, the feature detectors (FDs) discovered by our supervised systems resemble those found by our old unsupervised methods such as Predictability Minimization [2e,2g,2h] and Low-Complexity Coding and Decoding (LOCOCODE)[2i].

Our new systems' feature detectors resemble 
  those found by our old unsupervised methods such as
Predictability Minimization (1992). Jürgen Schmidhuber FD due to semi- linear PM [2e, 2g, 2h]


More Deep Learning Web Sites:

Since Sept 2013: G+ posts on Deep Learning

2014: Deep Learning in Neural Networks: An Overview (invited survey, with a history of Deep Learning since the 1960s)

2014: Who Invented Backpropagation? (History of Deep Learning's central algorithm 1960-1981 and beyond)

Deep NNs win MICCAI 2013 Grand Challenge and 2012 ICPR Contest on Mitosis Detection (first Deep Learner to win a contest on object detection in large images)

Deep NNs win 2012 Brain Image Segmentation Contest (first image segmentation competition won by a feedforward Deep Learner)

2012: 8th international pattern recognition contest won since 2009

2011: First superhuman visual pattern recognition in a limited domain (twice better than humans, three times better than the closest artificial competitor, six times better than the best non-neural method)

2009: First official international pattern recognition contests won by Very Deep Learning (connected handwriting through LSTM RNNs: simultaneous segmentation and recognition)

1997: First purely supervised Very Deep Learner

JS' first Deep Learner of 1991 + Deep Learning Timeline 1962-2013 (also summarises the origins of backpropagation, still the central algorithm of Deep Learning)

1991: Fundamental Deep Learning Problem discovered and analysed and partially solved

2009 Computer Vision site (precursor of present site)

2013: Compressed Network Search for reinforcement learning RNN video game controllers (> 1,000,000 weights) learning from scratch, using high-dim visual input streams.
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IJCNN 2011 on-site Traffic Sign Recognition Competition (1st rank, 2 August 2011, 0.56% error rate, the only method better than humans, who achieved 1.16% on average; 3rd place for 1.69%) (Juergen Schmidhuber)

Our simple training algorithms for deep, wide, often recurrent, artificial neural networks similar to biological brains have won competitions on a routine basis and yield best known results on many famous benchmarks for computer vision, speech recognition, etc. Shown in this page are example images of traffic signs, Chinese characters, connected handwriting, human tissue, sliced brains, etc.
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We are currently experiencing a second Neural Network ReNNaissance (title of JS' IJCNN 2011 keynote) - the first one happened in the 1980s and early 90s. In many applications, our deep NNs are now outperforming all other methods including the theoretically less general and less powerful support vector machines (which for a long time had the upper hand, at least in practice). Check out the, in hindsight, not too optimistic predictions of our RNNaissance workshop at NIPS 2003, and compare the RNN book preface.

Some of the (ex-)members of our Deep Learning Team: Sepp Hochreiter, Felix Gers, Alex Graves, Dan Ciresan, Ueli Meier, Jonathan Masci. For medical imaging, we also work with Alessandro Giusti in the group of Luca Maria Gambardella.

Our work builds on earlier work by great pioneers including Ivakhnenko, Bryson, Kelley, Dreyfus, Linnainmaa, Werbos, Fukushima, Amari, LeCun, Rumelhart, Hinton, Williams, Weng, von der Malsburg, Kohonen, and others (more history here and especially in this historical survey).

GPUs used for the work described in: High-Performance Neural Networks for Visual Object Classification, arXiv:1102.0183v1 [cs.AI]. (Juergen Schmidhuber) SELECTED DEEP LEARNING PUBLICATIONS
(many more here):

[26] J. Schmidhuber. Deep Learning in Neural Networks: An Overview. Preprint IDSIA-03-14 / arXiv:1404.7828 [cs.NE]. Version v3 (PDF, 2 July 2014). LATEX source. Complete public BIBTEX file. (Older versions: v1 of 30 April; v1.5 of 15 May; v2 of 28 May.) Invited survey, 75 pages, 866 references. HTML.

[25] J. Koutnik, K. Greff, F. Gomez, J. Schmidhuber. A Clockwork RNN. Proc. 31st International Conference on Machine Learning (ICML), p. 1845-1853, Beijing, 2014. Preprint arXiv:1402.3511 [cs.NE].

[24] R. K. Srivastava, J. Masci, S. Kazerounian, F. Gomez, J. Schmidhuber. Compete to Compute. In Proc. Neural Information Processing Systems (NIPS) 2013, Lake Tahoe. PDF.

[23] D. Ciresan, J. Schmidhuber. Multi-Column Deep Neural Networks for Offline Handwritten Chinese Character Classification. Preprint arXiv:1309.0261, 1 Sep 2013.

[22] J. Masci, A. Giusti, D. Ciresan, G. Fricout, J. Schmidhuber. A Fast Learning Algorithm for Image Segmentation with Max-Pooling Convolutional Networks. ICIP 2013. Preprint arXiv:1302.1690. On object detection in large images, now scanned by our deep networks 1500 times faster than with previous methods.

[21] A. Giusti, D. Ciresan, J. Masci, L.M. Gambardella, J. Schmidhuber. Fast Image Scanning with Deep Max-Pooling Convolutional Neural Networks. ICIP 2013. Preprint arXiv:1302.1700

[20] D. Ciresan, A. Giusti, L. M. Gambardella, J. Schmidhuber. Mitosis Detection in Breast Cancer Histology Images using Deep Neural Networks. MICCAI 2013. PDF.

[19] D. Ciresan, U. Meier, J. Schmidhuber. Transfer Learning for Latin and Chinese Characters with Deep Neural Networks. Proc. IJCNN 2012, p 1301-1306, 2012. PDF. Pretrain on one data set, profit on another.

[18] D. C. Ciresan, U. Meier, J. Masci, J. Schmidhuber. Multi-Column Deep Neural Network for Traffic Sign Classification. Neural Networks 32, p 333-338, 2012. PDF of preprint. (First superhuman visual pattern recognition.)

[17] D. C. Ciresan, U. Meier, J. Schmidhuber. Multi-column Deep Neural Networks for Image Classification. IEEE Conf. on Computer Vision and Pattern Recognition CVPR 2012, p 3642-3649, 2012. PDF. Longer preprint arXiv:1202.2745v1 [cs.CV].

[16] J. Masci, U. Meier, D. Ciresan, G. Fricout, J. Schmidhuber. Steel Defect Classification with Max-Pooling Convolutional Neural Networks. Proc. IJCNN 2012. PDF.

[15] D. Ciresan, A. Giusti, L. Gambardella, J. Schmidhuber. Deep Neural Networks Segment Neuronal Membranes in Electron Microscopy Images. In Advances in Neural Information Processing Systems (NIPS 2012), Lake Tahoe, 2012. PDF. (See also ISBI EM Competition Abstracts.)

[14] J. Nagi, F. Ducatelle, G. A. Di Caro, D. Ciresan, U. Meier, A. Giusti, F. Nagi, J. Schmidhuber, L. M. Gambardella. Max-Pooling Convolutional Neural Networks for Vision-based Hand Gesture Recognition. Proc. 3rd IEEE Intl. Conf. on Signal & Image Processing and Applications (ICSIPA), Kuala Lumpur, 2011. PDF.

[13] J. Schmidhuber, D. Ciresan, U. Meier, J. Masci, A. Graves. On Fast Deep Nets for AGI Vision. In Proc. Fourth Conference on Artificial General Intelligence (AGI-11), Google, Mountain View, California, 2011. PDF. Video.

[12] D. C. Ciresan, U. Meier, L. M. Gambardella, J. Schmidhuber. Convolutional Neural Network Committees For Handwritten Character Classification. 11th International Conference on Document Analysis and Recognition (ICDAR 2011), Beijing, China, 2011. PDF.

[11] U. Meier, D. C. Ciresan, L. M. Gambardella, J. Schmidhuber. Better Digit Recognition with a Committee of Simple Neural Nets. 11th International Conference on Document Analysis and Recognition (ICDAR 2011), Beijing, China, 2011. PDF.

[10] D. C. Ciresan, U. Meier, J. Masci, J. Schmidhuber. A Committee of Neural Networks for Traffic Sign Classification. International Joint Conference on Neural Networks (IJCNN-2011, San Francisco), 2011. PDF.

[9] D. C. Ciresan, U. Meier, L. M. Gambardella, J. Schmidhuber. Handwritten Digit Recognition with a Committee of Deep Neural Nets on GPUs. ArXiv Preprint arXiv:1103.4487v1 [cs.LG], 23 Mar 2011.

[8] D. C. Ciresan, U. Meier, J. Masci, L. M. Gambardella, J. Schmidhuber. Flexible, High Performance Convolutional Neural Networks for Image Classification. International Joint Conference on Artificial Intelligence (IJCAI-2011, Barcelona), 2011. PDF. ArXiv preprint, 1 Feb 2011. Describes our special breed of GPU-based max-pooling convolutional networks (GPU-MPCNNs), now widely tested/used by research labs (e.g., Univ. Toronto/Google/Stanford) and companies (e.g., Apple) all over the world.

[6] D. C. Ciresan, U. Meier, L. M. Gambardella, J. Schmidhuber. Deep Big Simple Neural Nets For Handwritten Digit Recognition. Neural Computation 22(12): 3207-3220, 2010. ArXiv Preprint arXiv:1003.0358v1 [cs.NE], 1 March 2010. Best results on MNIST with plain backprop for standard NNs (no unsupervised pre-training, no convolution etc).

[5] A. Graves, A. Mohamed, G. E. Hinton. Speech Recognition with Deep Recurrent Neural Networks. ICASSP 2013, Vancouver, 2013. PDF.

[4] A. Graves, J. Schmidhuber. Offline Handwriting Recognition with Multidimensional Recurrent Neural Networks. Advances in Neural Information Processing Systems 22, NIPS'22, p 545-552, Vancouver, MIT Press, 2009. PDF.

[3] A. Graves, S. Fernandez, J. Schmidhuber. Multi-Dimensional Recurrent Neural Networks. Intl. Conf. on Artificial Neural Networks ICANN'07, 2007. Preprint: arxiv:0705.2011. PDF.

[3a] A. Graves, S. Fernandez, F. Gomez, J. Schmidhuber. Connectionist Temporal Classification: Labelling Unsegmented Sequence Data with Recurrent Neural Networks. ICML 06, Pittsburgh, 2006. PDF.

Selected papers from the previous millennium (more here):

[2j] F. A. Gers, J. Schmidhuber, F. Cummins. Learning to Forget: Continual Prediction with LSTM. Neural Computation, 12(10):2451-2471, 2000. PDF.

[2i] S. Hochreiter and J. Schmidhuber. Feature extraction through LOCOCODE. Neural Computation 11(3): 679-714, 1999. PDF. HTML (some pictures missing).

[2h] N. N. Schraudolph, M. Eldracher, J. Schmidhuber. Processing Images by Semi-Linear Predictability Minimization. Network, 10(2): 133-169, 1999. PDF.

[2g] J. Schmidhuber and M. Eldracher and B. Foltin. Semilinear predictability minimzation produces well-known feature detectors. Neural Computation, 8(4):773-786, 1996. PDF . HTML. Facilitating supervised Bayes-optimal classification through unsupervised pre-training. Mentions a hierarchy of unsupervised PM stages.

[2f] J. Schmidhuber and D. Prelinger. Discovering predictable classifications. Neural Computation, 5(4):625-635, 1993. PDF. HTML. Compare "Siamese networks".

[2e] J. Schmidhuber. Learning factorial codes by predictability minimization. Neural Computation, 4(6):863-879, 1992. PDF. HTML. Partially motivated by speeding up supervised learning through unsupervised pre-processing.

[2d] S. Hochreiter, J. Schmidhuber. Long Short-Term Memory. Neural Computation, 9(8):1735-1780, 1997. PDF. Led to a lot of follow-up work, and is now used by leading IT companies all over the world.

[2c] J. Schmidhuber. Habilitation thesis, TUM, 1993. PDF. An ancient experiment with credit assignment across 1200 time steps or virtual layers and unsupervised pre-training for a stack of recurrent NNs can be found here - try Google Translate in your mother tongue.

[2b] S. Hochreiter. Untersuchungen zu dynamischen neuronalen Netzen. Diploma thesis, TUM, 1991 (advisor J.S.) PDF.

[2a] J. Schmidhuber. Learning complex, extended sequences using the principle of history compression, Neural Computation, 4(2):234-242, 1992 (based on TR FKI-148-91, 1991). PDF.

[1b] J. Schmidhuber. A local learning algorithm for dynamic feedforward and recurrent networks. Connection Science, 1(4):403-412, 1989. PDF. HTML. Local competition in the Neural Bucket Brigade (figures omitted).

Link to the first artificial fovea sequentially steered by a learning neural controller (1990). Jürgen Schmidhuber Ongoing work on active perception. While Deep Learning methods tend to work fine in many applications, they are passive learners - they do not learn to actively search for the most informative parts of the sensory input. Humans, however, use sequential gaze shifts for visual pattern recognition. This can be much more efficient than the fully parallel one-shot approach. That's why we want to combine the algorithms above with variants of our old method of 1990 [1a] - back then we built what to our knowledge was the first artificial fovea sequentially steered by a learning neural controller. Without a teacher, it used a variant of reinforcement learning to create saccades and find targets in a visual scene (and to track moving targets), although computers were a million times slower back then:

[1a] J. Schmidhuber, R. Huber. Learning to generate artificial fovea trajectories for target detection. International Journal of Neural Systems, 2(1 & 2):135-141, 1991 (figures omitted). Based on TR FKI-128-90, 1990. PDF. HTML. HTML overview with figures.

More on active learning without a teacher in the overview pages on the Formal Theory of Creativity and Curiosity.


News of 26 Jan 2014: Google acquired for reportedly $500 million the startup company deepmind co-founded by our former PhD student Shane Legg (PDF of thesis), Demis Hassabis, and Mustafa Suleyman. Deepmind focuses on general purpose learning algorithms (more on our work on this here), and also employs Schmidhuber's former PhD students Daan Wierstra (#4 of deepmind) & Tom Schaul & Alex Graves, who have been working on our deep RNNs: Alex on supervised RNNs, Daan & Tom on RL RNNs and Evolving RNNs (see their papers under the links above). Alex & Daan are also co-authors of one of the earliest deepmind publications (Dec 2013); compare our Compressed Network Search for RNN video game controllers learning from high-dim visual input streams (July 2013). See this news link.


Copyright notice (2013): This web page was derived from the computer vision page. Fibonacci web design by Jürgen Schmidhuber, who will be delighted if you use this web page for educational and non-commercial purposes, including articles for Wikipedia and similar sites, provided you mention the source and provide a link. Last update July 2014.
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My First Deep Learning System of 1991 + Deep Learning Timeline 1962-2013

COMPETITION DETAILS

Links to the original datasets of competitions 1-9 and benchmarks A-D mentioned in the leftmost column, plus more information on the world records set by our team:

Deep Learning Wins MICCAI 2013 Grand Challenge on Mitosis Detection

9. 22 Sept 2013: our deep and wide MC GPU-MPCNNs [8,17,18] won the MICCAI 2013 Grand Challenge on Mitosis Detection (important for cancer prognosis etc). This was made possible through the efforts of Dan and Alessandro [20]. Do not confuse this with the earlier ICPR 2012 contest below! Comment: When we started our work on Very Deep Learning over two decades ago, limited computing power forced us to focus on tiny toy applications to illustrate the benefits of our methods. How things have changed! It is gratifying to observe that today our techniques may actually help to improve healthcare and save lives.

Deep Learning Neural Networks are the best artificial offline recognisers of Chinese characters from the ICDAR 2013 competition (3755 classes), approaching human performance

D. As of 1 Sep 2013, our Deep Learning Neural Networks are the best artificial offline recognisers of Chinese characters from the ICDAR 2013 competition (3755 classes), approaching human performance [23]. This is relevant for smartphone producers who want to build phones that can translate photos of foreign texts and signs. As always in such competitions, GPU-based pure supervised gradient descent (40-year-old backprop) was applied to deep and wide multi-column networks with interleaving max-pooling layers and convolutional layers (multi-column GPU-MPCNNs) [8,17]. Many leading IT companies and research labs are now using this technique, too.

ICPR 2012 Contest on Mitosis Detection in Breast Cancer Histological Images

8. ICPR 2012 Contest on Mitosis Detection in Breast Cancer Histological Images (MITOS Aperio images). There were 129 registered companies / institutes / universities from 40 countries, and 14 results. Our team (with Alessandro & Dan) clearly won the contest (over 20% fewer errors than the second best team, first Deep Learner to win a contest on object detection). See ref [20], as well as the later MICCAI 2013 Grand Challenge above.

Deep Learning Wins 2012 Brain Image Segmentation Contest

7. ISBI 2012 Segmentation of neuronal structures in EM stacks challenge. See the TrakEM2 data sets of INI. Our team won the contest on all three evaluation metrics by a large margin, with superhuman performance in terms of pixel error (March 2012) [15]. (First pure image segmentation competition won by a Deep Learner; ranks 2-6 for researchers at ETHZ, MIT, CMU, Harvard.) This is relevant for the recent huge brain projects in Europe and the US, which try to build 3D models of real brains.

Deep Learning in Neural Networks: An Overview - draft of invited paper

6. IJCNN 2011 on-site Traffic Sign Recognition Competition (1st rank, 2 August 2011, 0.56% error rate, the only method better than humans, who achieved 1.16% on average; 3rd place for 1.69%) [10,18]. The first method ever to achieve superhuman visual pattern recognition on an important benchmark (with secret test set known only to the organisers). This is obviously relevant for self-driving cars.

who invented backpropagation?

5. The Chinese Handwriting Recognition Competition at ICDAR 2011 (offline). Our team won 1st and 2nd rank (CR(1): 92.18% correct; CR(10): 99.29% correct) in June 2011.

4. INI @ Univ. Bochum's online German Traffic Sign Recognition Benchmark (the qualifying), won through late night efforts of Dan & Ueli & Jonathan (1st & 2nd rank; 1.02% error rate, January 2011) [10]. More.

Recurrent Neural Networks, especially LSTM

C. The MNIST dataset of NY University, 1998. Our team set the new record (0.35% error rate) in 2010 [6] (through plain backprop without convolution or unsupervised pre-training), tied it again in January 2011 [8], broke it again in March 2011 (0.31%) [9], and again (0.27%, ICDAR 2011) [12], and finally achieved the first human-competitive result: 0.23% [17] (mean of many runs; many individual runs yield better results, of course, down to 0.17% [12]). This represented a dramatic improvement, since by then the MNIST record had hovered around 0.4% for almost a decade.

B. NORB object recognition dataset for stereo images, NY University, 2004. Our team set the new record on the standard set (2.53% error rate) in January 2011 [8], and achieved 2.7% on the full set [17] (best previous result by others: 5%).

A. The CIFAR-10 dataset of Univ. Toronto, 2009. Our team set the new record (19.51% error rate) on these rather challenging data in January 2011 [8], and improved this to 11.2% [17].

Deep Learning Wins Three Connected Handwriting Recognition Competitions at ICDAR 2009

Three Connected Handwriting Recognition Competitions at ICDAR 2009 were won by our multi-dimensional LSTM recurrent neural networks [3,3a,4] through the efforts of Alex. This was the first RNN system ever to win an official international pattern recognition competition. To our knowledge, this also was the first Very Deep Learning system ever (recurrent or not) to win such contests:

3. ICDAR 2009 Arabic Connected Handwriting Competition of Univ. Braunschweig

2. ICDAR 2009 Handwritten Farsi/Arabic Character Recognition Competition

1. ICDAR 2009 French Connected Handwriting Competition (PDF) based on data from the RIMES campaign

Note that 1-3,C,D are treated in more detail in the page on handwriting recognition.

Here a 12 min Google Tech Talk video on fast deep / recurrent nets (only slides and voice) at AGI 2011, summarizing results as of August 2011:

Google Tech Talk video (13:05) on fast deep / recurrent neural networks for computer vision presented by Juergen Schmidhuber at AGI 2011 at Google HQ, Mountain View, CA.

People keep asking: What is the secret of your successes? There are actually two secrets:

(i) For competitions involving sequential data such as video and speech we use our deep (stacks [2a] of) multi-dimensional [3] Long Short-Term Memory (LSTM) recurrent networks (1997) [2d,2j] trained by Connectionist Temporal Classification (CTC, 2006) [3a]. This is what since 2009 has set records in recognising connected handwriting [4] and speech, e.g., [5].

(ii) For other competitions we use multi-column (MC) committees [10] of GPU-MPCNNs (2011) [8], where we apply (in the style of LeCun et al 1989 & Ranzato et al 2007) efficient backpropagation (Linnainmaa 1970, Werbos 1981) to deep Neocognitron-like weight-replicating convolutional architectures (Fukushima 1979) with max-pooling (MP) layers (Weng 1992, Riesenhuber & Poggio 1999). Over two decades, LeCun's lab has invented many improvements of such CNNs. Our GPU-MPCNNs achieved the first superhuman image recognition results (2011) [18], and were the first Deep Learners to win contests in object detection (2012) and image segmentation (2012), which require fast, non-redundant MPCNN image scans [21,22].

For more information on how we have built on the work of earlier pioneers since the 1960s, see www.deeplearning.me and especially this historical survey).

Sepp Hochreiter's Fundamental Deep Learning Problem (1991)

Our algorithms not only were the first Very Deep Learners to win official international competitions (since 2009) and to become human-competitive, they also have numerous immediate industrial and medical applications. Apple & Google and many others adopted our techniques. Are you an industrial company that wants to solve interesting pattern recognition problems? Don't hesitate to contact JS. We already developed:

1. State-of-the-art handwriting recognition for a software services company.
2. State-of-the-art steel defect detection for the world's largest steel maker.
3. State-of-the-art low-cost pattern recognition for a leading automotive supplier.
4. Low-power variants of our methods for apps running on cell phone chips.

See this recent youtube video (14 April 2014) of a talk at ETHZ on Deep Learning, with slides:

Juergen Schmidhuber's Talk on Deep Learning at the ETHZ ML meetup (14 April 2014)
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