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TS1 TEXTURES Creating textures using Photogrammetry, of areas in Middlesbrough.
INTRODUCTION
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PROCESS
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TEXTURES
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EVALUATION
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INTRODUCTION
Introduction
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Photogrammetry is the process of taking multiple images of an object or area, to generate measurements.
Process
Textures
Evaluation
You can see the locations and all images captured by clicking below:
These can then be used to create maps, 3D models and textures.
50% of each image must overlap with the last.
PHOTOS were all taken using an iPad mini.
76 was the highest amount of images taken for the wall.
BARK had the least photos with only 14.
Software used:
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PROCESS
Introduction
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Process
Textures
Evaluation
IMPORT
ALIGN
When taking photos each image must roughly overlap 50% with the last one taken.
It’s then important to identify which pictures are of a good enough quality to be used.
The align tool stitches all the images together by recognising areas of repetition and placing them in order.
The next step is to build the dense cloud, this uses the aligned result to produce a higher resolution variant.
It is also helpful to take photos on days where it is overcast, to keep the lighting in each image consistent.
In Agisoft Photoscan I used the ‘Estimate Image Quality’ to find and remove any image lower than 0.5.
Here, you can begin to see the wall pattern forming.
This can then be used to create a mesh, which will be used later on in the bake.
PHOTO
BUILD
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PROCESS
Introduction
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MESH
TEXTURE
Process
LOW POLY
Textures
Evaluation
PROJECT
Before
After
There are two options when creating the mesh: Arbitary and Heightfield.
The texture will appear blurred after creating the mesh.
In 3DS Max, I displaced a plane to fit over the high poly mesh.
Arbitary creates a full better quality 3D model, whereas heightfield is a 2.5D plane – which is suited for simple flat textures.
Using the high poly mesh you can create a high resolution variant of this texture for use in the next sections.
Moving the vertices of the plane allowed me to edit what height information would be in the final bake.
I then baked the high to low poly mesh, with the base texture in order to create a flattened base colour and height map texture.
The next step is to make it tile able.
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PROCESS
Introduction
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TILE
REFINE
Process
BAKE
Textures
Evaluation
FINAL
Before
After
Both the height map and base colour were edited at the same time using masks in Photoshop. I selected the largest square I could, and then edited this using the warp tool to create a tile able texture.
In ZBrush the height map was added as a displacement map on a plane, to test if the effect was working correctly. I could then edit areas of the sculpt and export the finished model as my new high poly mesh.
Back in XNormal, I added the new high poly mesh and the low poly plane.
Finally the textures were assembled using Toolbag 3.
Using these I could then bake the normal, new heightmap and occlusion.
I set the subdivision to flat, and made some minor adjustments to the values to produce the finished image.
Any further modifications were made in CrazyBump.
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TEXTURES x
TEXTURES
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Introduction
Process
The next few pages show the texture breakdowns for each material.
Textures
Evaluation
BC – Base Colour N – Normal D – Displacement O – Occlusion S – Specular
Each material presented it’s own challenges, I will also detail how I overcame these. Unreal in-engine screenshot, testing each material set up.
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BARK
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BARK
Introduction
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Process
Textures
Evaluation
The bark images were captured from a top down perspective, because of this it stitched together very well. The organic nature of this material, also meant that it could be tiled with minimal editing.
BC
N
D
Because this is a noisy texture, I blurred the displacement map to reduce this issue.
Average Image Quality:
0.87 O
S
14
Capture Conditions:
photos in total.
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BRICKS
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BRICKS
Introduction
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Process
Textures
Evaluation
This was a challenging material. Although the wall is relatively flat, the area I scanned appears warped from different angles.
BC
N
D
This combined with the changing light conditions, made it a difficult texture to tile – and required warping in Photoshop.
Average Image Quality:
0.86 O
S
75
Capture Conditions:
photos in total.
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TREE BARK
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TREE BARK
Introduction
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Process
Textures
Evaluation
The bark presented some unique challenges, as all of the textures I created so far were from already flat objects.
BC
N
D
I approached this issue by using XNormal to bake information from the high poly to a displaced low poly plane. Using the outputted image I selected a square area to become the texture.
Average Image Quality:
0.85 46 O
S
Capture Conditions:
photos in total.
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GRASS
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GRASS
Introduction
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Process
Textures
Evaluation
This was another texture that could be captured from a top-down perspective, resulting in an easily tile able texture. The main issue is the blurring in the flowers, due to the wind, in each image they would be in a slightly different position.
BC
N
D
Average Image Quality:
0.84
O
S
15
Capture Conditions:
photos in total.
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EVALUATION
Introduction
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Process
Textures
Evaluation
This project was very enjoyable, it was surprising to see the quality and level of detail that could be produced in the final textures – by using just the iPad’s camera. I also particularly enjoyed learning the process of photogrammetry and using software like PhotoScan.
I would definitely consider using this process in future pieces of work.
Projecting the built brick texture, on to the mesh.
It would be interesting to see if stylised textures could be created by manipulating and applying filters in Photoshop.
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EVALUATION
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Introduction
Process
Textures
Evaluation
One of the main issues I had was with the capture of top-down textures. Because I was pointing the camera straight down my shoes ended up in almost every photo of the grass texture! This could of easily be avoided if I had proper camera equipment like a tripod.
Thankfully due to the way the software works, the shoes were placed on an edge of the texture, and could be cropped out. I often selected the best area of a built texture to work on further.
Nice shoe shaped blur.
Shoes sneaking in to every shot.
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EVALUATION
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Introduction
Process
Textures
Evaluation
The brick texture, was the first and most challenging piece. Due to the nature of the brick, it was difficult to tile and required a lot of warping and cloning to get it to match up.
I struggled to find a solution to this in Photoshop. The heightmap was particularly problematic as the lighting was very uneven and produced strange results.
1st attempt had obvious blurring where the textures was tiled.
In the end, I decided to use a combination of XNormal and CrazyBump to create the new heightmap. There was lots of variations.
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EVALUATION
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Introduction
Process
Textures
Evaluation
I set out on this project to improve my texturing abilities, and investigate new techniques I could incorporate in to my work. By working briefly in Substance Designer and following some tutorials, I was able to improve my knowledge on what goes into a material – before moving on to the photogrammetry. If I were to attempt this again, I would like to try using higher quality equipment, and using a larger amount of photos.
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