Yes,

1- you can scanner she topographic sheets

2- to register the coordinates corner

3- transformer the raster in vector inside of an software of DPI.

1 - create drafts for all themes of interest for you (e.g., hydrology, forests, cities) in separate mylar sheets by using a very thin pen (e.g., rotring); include as accurately as possible the control points (e.g., corners with known coordinates) on each sheet (use a cross sign);

pay attention at common arcs for different themes (e.g., borders between a river and a forest); it is better to put them only on one mylar sheet (e.g., on hydrology mylar sheet) and copy their digital version on the other layers at step 4 below

2- now, scan the drafts at an appropriate resolution to keep all the original inf.

3- use an automated software for thinning and vectorizing; in my experience, GRASS performs a very good job; you have n layers at this step (n=number of themes of interest)

4-copy the common arcs

If you can obtain the originals of edition of your topographic map, you can go directly to step 3 ! Good luck !

I used to obtain the topographic contours in an automatic way, from the SRTM DEM (90 meters spatial resolution). It depends on the work scale that you need.

Vanesa,

My recommendations above presume that the topographic sheets are on paper. That is why the digital data collection needs several steps. Conversely, if data are already in raster format, as SRTM you've mentioned, that means they are already in a digital form. If I understand well the question of Sharma, his real problem is to separate different themes of an analogue topographic map. In my opinion, this has to be done manually (if the originals of edition aren't available), prior to the automatic acquisition of the themes. Therefore, I don't recommend a 100% automation. Instead, the data for digitization (i.e., for scanning->thinning->vectorization) should be prepared in advance, such as each theme is drawn on a separate mylar sheet (generating clear chloropleth & isopleth maps, without any annotation from the analogue map). Rationale: The accuracy of the digital topographic maps is always critical, as they serve as reference for applications. On the other hand, a fully automatic collection in digital form of the analogue topographic maps may lead to errors, which are more time consuming to correct (anyway, somebody will do this !) than the solution I've suggested. This is my experience.

Thank you very much! Even if I derive these automatically from DEM, I guess to check the accuracy/quality I should follow Ruxandra's suggestion (?)

Shama,

If you decide to automatically derive elevation contours from a DEM:

- the positional accuracy will depend on the DEM's cell size and the algorithm used for the transformation raster->vector

- the thematic accuracy will mainly depend on how a particular DEM was generated; it is worth mentioning that currently available DEMs (e.g., SRTM) were generated at a finer resolution (30 m for SRTM) than the ones freely available (90m for SRTM, as already Vanesa mentioned); so, to assess the thematic accuracy of your final digital map, in the actual case of the DEM you are using, if it is the case you should find out how the spatial degradation was performed at the level of attributes ; for example, I know that in the case of GTOPO30 (another freely available DEM) the elevation assigned to each 30 arc-seconds cell is the median value of the original values (measured or estimated at a finer spatial resolution than 30 arc- seconds) included in that cell.

@ Ruxandra Thank you. I shall keep your advice in mind and work on it.

Sharma Rux advise is great. If you further want you can generate 30 m and 15m resolution DEM using ASTER data and coregister it with SRTM. We tried it for Kuwait and it worked well. see out papers on RG, they might help you.

Scan the map sheet, digitize contour as as lines(.shp), Open Attribute table and Add Field (specify it as Float), name the field as Heights or Elevations, then Feed in the contour height readings as shown from the hard copy(map sheet). It will behave as the countors created from DEM, from here you can manipulate from Coutour to TIN,DEM etc. Good lucky

I assume you are Using ArcGIS 9.x

Yes and no. We often have to deal with old maps, and sometimes it works via Adobe Illustrator, sometimes im ArcGIS. But in most cases the result -depending on the base data- will not be good enough. Better do it by scanning, georeferencing and digitizing by hand.

When using recent data such as DEM or SRTM be aware that the landscape only represents the recent situation. For earlier landscape impressions you need to use older maps to digitize and recalculate with the recent data. We are working with ArcGIS 10.x

The ASTER and STRM dems are great alternatives. Although there are few commercially available softwares that can help in automatic scanning and digitization.

Its possible with clean and high resolution scanning . Practically not possible. Vintila's answer is correct :)

@everyone Thanks.

Automatically we can delineate from DEM using ArcGIS

Another alternative in arcGIS is ArcScan module. Corel trace is also a powerfull tool for vector to raste transformations.

This makes the program Spotlight (http://www.rasterarts.ru/) or module ArcScan in ArcGIS.

long ago I visited a website where a tool called "blackart" was downloadable. It took a raster topographic map as input, process it based on colours, isolate contours (which are usually brownish in colour, atleast in SOI toposheets), thin the contours, then vectorise (automatic). But some manual input was needed in the middle, for connecting contours, where they were intersected by other features. tried it, but felt that for very complex toposheets it may not work well. don't know if it's available now.

It still exists:

http://www.terrainmap.com/rm33.html

Well, you can go this way also via Adobe Illustrator by classifying the Maps so that you will have only the lines selected, but afterwards you have lot of work with control all features and editing them.

Jorg guess Haris has suggested a better alternative.

R2V and Didger softwares

Practically It is done like-

1. It is not possible to scan toposheet to the quality where it becomes possible to auto vectorise it as weight used is very fine.

2. we can achieve it by tracing contours on tracing paper with proper weight of rotring pen.

3. Scan and use R2V (courtesy Vladimir)

4. Its all done.. without errors. 

I have seen automatic contour digitalization in the Photomod software

You can generate the contours automatically in ArcGIS by using a SRTM Digital Elevation Model as data source.

Many photogrammetry software can extract contour lines from DTM automatically. The smoothness and visibility  are different from manually working definitely. Yes,as some one said,Photomod performances good.CloudEo provides a cloud workbench with this software,could be a good solution for you in short time use:https://store.cloudeo-ag.com/photomod-workbench-academia