From Scratch to SOTA: Training a 3B State-Space Vision Model — Krishna Prasad Srinivasan, Sarvam

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00:00:00all right hi everyone graph known I'm Krishna and I'm a general manager at server today I'm
00:00:24going to tell you how a three billion parameter model small enough to run on a single GPU gets
00:00:32state-of-the-art in document AI and beats models a hundred times larger in size it is also a slightly
00:00:42unusual model in two ways firstly the language model used is not a standard transformer and the
00:00:49entire model building from data to training to compute was done end-to-end in India and for
00:00:58English and for 22 official Indian languages which I think are personally one of the hardest document
00:01:06intelligence problems in the world right now this is how we went from scratch to SOTA who are we we are
00:01:15servom a sovereign foundation model company in India we work across different modalities voice text and
00:01:23vision invoice we have speech-to-text and text-to-speech models in text we have a 30 billion and a hundred
00:01:32billion parameter models and in vision we have a document intelligence model which is what we are
00:01:38going to talk about today India is largely missing from the machine-readable world according to a published
00:01:48language distribution study well under one percent of the common crawl corpus on which frontier models are
00:01:55trained have Indian language representation now in several forums you may have heard frontier lab say that
00:02:04India is there India is one of their larger and fastly growing markets and to that end India is still missing in terms of data from
00:02:16frontier models that are being trained every day here now why is that primarily not because there is a lack of data or the knowledge does not exist it is because the data has never been digitized and
00:02:31the data has never been digitized and we are solving that problem at Servum why is Indic document intelligence hard
00:02:38firstly the goal is that of knowledge extraction not just purely text extraction extracting pure text without
00:02:49logical coherence is meaningless and secondly in Indic scripts the shape of the words and the language you see are very different from what a
00:03:01machine sees that is Indian languages have a complex set of unicodes fused together to get right the language model needs to be strong at all 22 languages
00:03:13third majority of Indian languages can be considered low resource due to which there is a lot of lack in data today to train these models
00:03:23So our answer to this is Servum vision India's first sovereign vision language model built from scratch a 3 billion parameter model with state space architecture data compute and training all of which done in India
00:03:40When we started the initial work in late 2025 most VLMs in the OCR space were monolith VLMs they performed page level OCR and we at the time took a contrarian bet to focus on block level OCR instead adding a document hardness around the model
00:04:02A lot of models since then released recently in 2026 have converged onto the same hardness plus small model paradigm for OCR which shows a lot of value in the direction we set off
00:04:17Servum vision in particular has two hardness modules one for layout and one for reading hardness and a state space model VLM for block level OCR
00:04:29Again, today, why do we use state space and not a transformer?
00:04:36Most OCR models today, like general VLMs, open source VLMs like Quen, Gemma, etc. are all transformers based
00:04:45We took an alternate approach using an SSM. Why?
00:04:50Both are fundamentally sequenced models, transformers and SSMs, but with very different underlying mechanics
00:04:57A transformer has every token look at every other token where the compute grows with square of the sequence length
00:05:06That is the L cross L interactions
00:05:10And the memory goes as the sequence grows as well
00:05:13Now, on the other hand, SSMs have a single state
00:05:17They maintain a single state through the sequence updating it token by token
00:05:22Now, as compute grows only linearly, the memory stays constant for SSMs
00:05:27Now, why is this the right architecture for OCR?
00:05:32It really depends on the trade-offs here for long documents in particular, which can lead up to 5,000 to 10,000 visual tokens per page
00:05:43And quadratic complexity of, you know, compute and memory becomes very expensive for inference
00:05:51On the other hand, doing block level OCR with somewhat of a lossy recall using SSMs can be justified
00:06:00To avoid high compute costs imposed by transformers
00:06:08So, how do you actually train this?
00:06:10We built a staged curriculum, four stages
00:06:13Each building on the last stage one is text-only pre-training
00:06:1913 trillion tokens across English, Indian language text, math, and code
00:06:25This builds the 3 billion parameters language backbone
00:06:29And a strong language prior is what lets the model resolve a smudged or an ambiguous text from the image
00:06:38The same way you can read a half-blurred word
00:06:41Because you know which word is supposed to be at the right place
00:06:46So, we focused on building the competence of the language model first
00:06:51Before the model ever even sees a pixel
00:06:54Stage two is where we perform continual pre-training on 300 million image text pairs
00:07:01This teaches the language model general vision capabilities
00:07:05And teaches how to see, how to interpret pixels, and so on
00:07:08Then comes stage three where we performed supervised fine-tuning on 100 million OCR
00:07:15Now, stage three is primarily focused on letting a general VLM model become strong at OCR
00:07:26What that includes is having diverse data across all 22 languages and English
00:07:32And also incorporating all kinds of document components such as tables
00:07:39And equations and handwritten documents and so forth
00:07:44And stage four is reinforcement learning which helps push past the ceiling of whatever supervised fine-tuning is able to achieve
00:07:54Here, you will see this is a standard recipe
00:07:57However, the moat here is the two things underneath
00:08:02The data layer and the eval layer
00:08:05The first is the data engine
00:08:08For most of the 22 languages, there is no label data available readily
00:08:13When label data does not exist, building the data engine becomes hard
00:08:18And that is something we have done extensively
00:08:21We have built pipelines to create synthetic data and data from real documents
00:08:26And also helped build the pipeline for continuously improving the data that goes into training
00:08:35Based on the eval performance and so on
00:08:37So, we are currently actively looking at the paradigm of RLMs
00:08:42As we explore the agent vision capabilities for our models in the upcoming releases
00:08:48The second moat is the evals
00:08:51You cannot reach state-of-the-art if you cannot measure how well your model performs
00:08:57We have curated extensive evals to ensure what we are measuring is truly SOTA
00:09:03And also truly meaningful in terms of usefulness for end users
00:09:09So, I want to take just a minute to dwell on our RL pipeline
00:09:15Stage four, because a lot of gain comes from RL essentially
00:09:20In OCR, correctness is a machine-readable problem, right?
00:09:24A lot of tests can be set up to reward and score the models
00:09:30These samples that you create
00:09:34And in the world of deterministic OCR
00:09:37These are all machine-verifiable
00:09:40Hence, RL gives us a major boost
00:09:44Sample a group
00:09:45Score with unit tests
00:09:47Reinforce what the average value-to-beat is
00:09:51And then repeat the process
00:09:53And this makes RL-VR for OCR very, very scalable
00:09:57Now, after all the from-scratch training we've done
00:10:01And the data effort we've made
00:10:03We were able to establish SOTA in two of the global English benchmarks
00:10:08One is OCR Bench
00:10:10And the other is Omnidoc Bench
00:10:12At launch, we were at 84.3 on OCR
00:10:15And then 93.2 on Omnidoc Bench
00:10:18The models that have released since
00:10:22Have moved the needle quite a bit
00:10:24And we'll soon have a stronger model
00:10:26In the global leaderboard as well
00:10:29Secondly, and more importantly
00:10:31On 22 Indian languages
00:10:34We have an unbeaten lead
00:10:36Even compared to all the frontier models
00:10:38Such as Gemini
00:10:40And ChatGPT
00:10:41And Opus
00:10:42And so on
00:10:43And this is where we've extended the lead significantly
00:10:46And we remain strong
00:10:48Compared to all of these newer models
00:10:50That have come in
00:10:52Now, Servum Vision
00:10:54Parse our agentic document intelligence workbench
00:10:57Called Akshar
00:10:59Where we enable
00:11:01Human-in-the-loop agentic digitizations
00:11:04And extractions
00:11:06And then ingestions
00:11:07For various downstream document intelligence problems
00:11:11We provide confidence scores
00:11:13And we have block-level grounding
00:11:16And then also the ability to do agentic proofreading, etc.
00:11:22Now, benchmarks and SOTA are one thing
00:11:26They have their place
00:11:27Today, some of the largest enterprises in the world
00:11:30From insurance to banking
00:11:32To governments
00:11:33To historical preservation organizations
00:11:36Are using Servum Vision
00:11:38To digitize more than 35 million pages
00:11:40Across English
00:11:41And 22 Indian languages
00:11:44The model is available as API
00:11:48And on-prem
00:11:49And then the agentic platform
00:11:51So, in conclusion
00:11:54Until four months ago
00:11:56There was no sovereign model from India
00:11:59Today, we have Servum Vision
00:12:02Which was trained from scratch
00:12:03And has established SOTA
00:12:06At a price point
00:12:07That is extremely competitive
00:12:09With all the other solutions
00:12:11Including open and closed source
00:12:14First, we have started by solving
00:12:16Some of the hardest problems
00:12:18For Indian language document intelligence
00:12:20Soon, we will be releasing
00:12:22General purpose VLMs
00:12:24Which are capable of much more
00:12:26Vision capabilities
00:12:28And look forward to
00:12:30All of you trying out our models
00:12:32Thank you
00:12:33Happy to answer any questions
00:12:35Happy to answer any questions
00:12:37Happy to answer any questions
00:12:38Happy to answer any questions
00:12:39Happy to answer any questions
00:12:39Happy to answer any questions
00:12:40Yeah
00:12:40Happy to answer any questions
00:12:41Happy to answer any questions
00:12:42Yeah
00:12:43Happy to answer any questions
00:12:44Yeah
00:12:45Happy to answer any questions
00:12:46Yes
00:12:47Yes
00:12:48Yes, absolutely
00:12:49In general
00:12:50The language capability
00:12:51Of the 22 languages
00:12:53Enhances English
00:12:54By quite a margin
00:12:56And this is applicable
00:12:58To any low-resource language
00:12:59Not just Indian low-resource languages
00:13:02Right
00:13:27We don't quite go in that direction
00:13:29With this model
00:13:30Because this is a vision-focused model
00:13:33Wherein we are focused
00:13:34On extracting information
00:13:35Or knowledge from documents
00:13:37But yes
00:13:38There could be
00:13:39Some parallels
00:13:40To helping models
00:13:42Use general languages
00:13:44To speed up coding
00:13:45As well
00:13:46But yeah
00:13:47That's not the
00:13:48Periphery of this work
00:13:50Yeah
00:13:53Right
00:13:54So there are two things
00:14:11We create artificial documents
00:14:14Synthetic documents
00:14:15As they are called
00:14:16For general post-training
00:14:18That includes
00:14:19SFT
00:14:20And RL
00:14:21However
00:14:22Coming to your specific question
00:14:23On RL
00:14:24We don't
00:14:25We don't
00:14:26You can generate
00:14:27Synthetic documents
00:14:28There as well
00:14:29However
00:14:30The best thing to do
00:14:31Is to take real-world documents
00:14:32Complex enough
00:14:33That
00:14:34That help you set up
00:14:35Unit tests
00:14:36Or different kinds
00:14:37Of rewards
00:14:39Right
00:14:40Like say
00:14:41A reward based on
00:14:42Character rate
00:14:43Or a reward based on
00:14:44Table structure
00:14:45Or a math equation
00:14:47Or something
00:14:48That is pertinent
00:14:49To a language
00:14:50Or like grammar rewards
00:14:51Or so on
00:14:52And then help
00:14:53The model
00:14:54Iteratively improve
00:14:55Based on
00:14:56Rule outs
00:14:57That the model is able
00:14:58To produce
00:14:58At different
00:14:59Settings
00:15:00Yeah
00:15:01Yes
00:15:20So did you say
00:15:21Big fan of Chandra?
00:15:22Yeah
00:15:23All right
00:15:24That's from a different lab
00:15:25I'm also a big fan
00:15:26Of the lab
00:15:27That produced Chandra
00:15:28But yes
00:15:29To your question
00:15:30On Indic Benchmark
00:15:31Yes
00:15:32We will release
00:15:33The Sarvam Indic Benchmark
00:15:34That we have created
00:15:36For 22 languages
00:15:37And it
00:15:38Spans
00:15:39A huge time period
00:15:42Starting from 1800s
00:15:43Until modern day
00:15:44And also
00:15:45Different kinds of layouts
00:15:46Different kinds of
00:15:47Documents
00:15:48In Indian languages
00:15:49You can imagine
00:15:49Documents
00:15:50With prose
00:15:51Poetry
00:15:52Literature
00:15:53Tables
00:15:53Finance
00:15:54And all of those things
00:15:54We will soon release
00:15:55That benchmark
00:15:56In public
00:15:57As well
00:15:57In public
00:15:59As well
00:16:00So
00:16:02Translation is again
00:16:02Transliteration is again
00:16:03Not directly involved here
00:16:03Because in OCR what we care about is high fidelity
00:16:05extraction
00:16:07Right
00:16:08You want
00:16:09You want
00:16:09Even if there is a mistake in an image
00:16:10You want that mistake in an image
00:16:11You want that mistake to be extracted correctly and not the model
00:16:15Making changes at whim
00:16:18Hence that is not directly applicable
00:16:19Hence that is not directly applicable but yes what we see is a lot of data
00:16:23That is a lot of data that is coming through transliteration for even OCR
00:16:25Training now
00:16:26And the jury is out on what you're going to do now and the jury is out on what you're going to do
00:16:28Do you want to do that?
00:16:29So
00:16:29Translateration is again not directly involved here because in OCR what we care about is high fidelity
00:16:33Extraction
00:16:35Right
00:16:36You want even if there is a mistake in an image you want that mistake to be extracted correctly and not the
00:16:40Model making changes at whim
00:16:43Hence that is not directly applicable but yes what we see is a lot of data that is coming through
00:16:49Transliteration for even OCR training now and the jury is out on what is the quality of that data and how useful it is etc
00:16:58Yeah
00:17:00Yes
00:17:01Yes
00:17:26Right
00:17:27There are a few things to consider
00:17:29First is no other model Frontier closed source or open model does well with complex Indian language documents
00:17:39Right
00:17:40So for a country with 1.4 billion people you want to be able to address their day-to-day lives in terms of document intelligence problems
00:17:52Because there is a lot of paperwork in India right
00:17:55It is a up and coming country and still being digitized as we speak and it's important that representation or ability to digitize the country exists to begin with
00:18:05Secondly on the training side what we have done in particular is to create data that can be added to a lot of training downstream
00:18:18So we are at a very early stage in terms of AI becoming you know a regular part of our lives and we need the data to start to be able to eventually get to a place where we can
00:18:31Have personalized agents in the language you prefer in language I prefer and however I want in some
00:18:38So to do all of that we need to start somewhere and the data needs to be created and if the data is of good quality then that helps the model become SOTA
00:18:47And if a model is SOTA then from insurance agencies to government organizations to others who care about sovereignty in AI right
00:18:58As a government body I cannot have a model deployed elsewhere and I don't know where the data is going for the transcriptions
00:19:06So I need to be able to control where the data is sent and when it is used how much it is used etc.
00:19:13So sovereignty becomes very crucial and hence this model really is now
00:19:17Like it's been what four months since we launched and already we are digitizing 35 million pages
00:19:23So that is that shows that the market was waiting for something sovereign in this space that can really kickstart the AI digitization wave in India
00:19:32So yeah primarily like three aspects one on sovereignty the other is the model capability itself and the third is data that is required to train these models
00:19:42Yeah it is it is 40% Indic and then the rest is English and comprises of math and code etc.
00:20:03All right
00:20:07All right
00:20:08Yes
00:20:09Just a serious question
00:20:24Currently the deployments we've made with this model are in different states
00:20:31Trying to digitize regional languages along with all the English and mixed language documents
00:20:39And hence we'll soon be able to train with the feedback we get from the current deployment
00:20:48So yeah we have started that pipeline as well
00:20:50And then we have started that pipeline as well

Key Takeaway

Sarvam Vision achieves state-of-the-art document intelligence across 22 Indian languages and beats giant models on global OCR benchmarks by using a 3B parameter state-space architecture trained on a 4-stage curriculum with machine-verifiable reinforcement learning.

Highlights

  • Sarvam Vision is a 3-billion parameter sovereign vision-language model trained entirely in India across English and 22 official Indian languages.

  • Using a state-space model (SSM) architecture instead of a transformer allows compute complexity to grow linearly rather than quadratically, maintaining constant memory for long documents.

  • The 4-stage training curriculum consists of 13-trillion-token text pre-training, 300-million image-text pair continual pre-training, 100-million OCR supervised fine-tuning, and machine-verifiable RL.

  • Sarvam Vision achieved top global benchmark scores of 84.3 on OCR Bench and 93.2 on Omnidoc Bench while maintaining an unbeaten lead in 22 Indian languages over models like Gemini and ChatGPT.

  • Over 35 million pages are being digitized across enterprise, government, and historical preservation deployments using Sarvam Vision and its Akshar workbench.

Timeline

The Indic Document Intelligence Challenge and Sarvam's Sovereign Approach

  • Under one percent of the Common Crawl corpus contains Indian language representation despite vast demographic demand.
  • Indic document intelligence requires logical knowledge extraction rather than simple raw text extraction.
  • Complex fused unicode script shapes and low-resource data scarcity make training Indic OCR models uniquely difficult.

India remains largely unrepresented in machine-readable datasets because historical and modern documents have never been systematically digitized. Extracting text from Indian languages involves multi-unicode character fusion where visual word shapes differ significantly from underlying machine representations. Sarvam addresses this gap as a sovereign foundation model company building native voice, text, and vision capabilities.

Architecture Choice: State-Space Models Versus Transformers

  • Monolith page-level OCR systems are inferior to block-level OCR paired with dedicated layout and reading hardness modules.
  • Transformers scale quadratically in compute and memory with sequence length, making high-resolution document OCR expensive.
  • State-space models maintain a single state updated token-by-token, keeping memory constant and scaling compute linearly.

Standard vision-language models process full document pages containing 5,000 to 10,000 visual tokens, resulting in massive computational overhead due to quadratic sequence interactions. By switching to a 3B parameter State-Space Model (SSM) architecture focusing on block-level extraction, inference costs drop significantly while retaining processing accuracy.

The Four-Stage Curriculum and Deterministic RL Moat

  • Pre-training begins on 13 trillion text tokens to build language priors before the model processes any visual pixels.
  • Stage two and three involve 300 million image-text pairs and 100 million OCR supervised fine-tuning pairs.
  • Deterministic OCR outputs enable machine-verifiable unit test rewards for scalable reinforcement learning.

A strong linguistic prior allows the model to resolve smudged or ambiguous text visually, similar to human reading context. After continual visual pre-training and fine-tuning across math, tables, handwriting, and 22 languages, stage four applies RL. Because document extraction correctness can be validated deterministically using unit tests for character rates and table structures, RL provides a scalable performance boost.

Benchmark Results, Enterprise Deployment, and Q&A Insights

  • Sarvam Vision achieved 84.3 on OCR Bench and 93.2 on Omnidoc Bench while holding the top position for 22 Indic languages.
  • Enterprises and government bodies currently use Sarvam Vision and the Akshar workbench to digitize over 35 million pages.
  • The pre-training dataset balance comprises 40% Indic content alongside English, math, and code.

Sarvam Vision powers Akshar, an agentic workbench featuring human-in-the-loop verification, block-level grounding, and confidence scoring. Sovereign data control is critical for government and enterprise adoption where privacy rules prevent off-shore data transfer. The team is also preparing to open-source the Sarvam Indic Benchmark covering historical and modern documents spanning from the 1800s to present day.

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