## 4 Discussion  
The analysis of the outcomes of acne scar treatment using an erbium glass laser demonstrated statistically significant changes in skin texture, as evidenced by alterations in the contrast and homogeneity parameters. Across all channels--red (R), green (G), blue (B), and the combined RGB--the treatment resulted in a decrease in contrast and an increase in homogeneity. These findings are consistent with the hypothesis that laser therapy effectively reduces the irregularities in skin texture that are associated with atrophic scars, leading to smoother and more uniform skin. The observed decrease in contrast signifies a reduction in the variability of the adjacent pixel intensities, which correlates with a flattening of irregularities and an improvement in the overall texture of the skin. Simultaneously, the increase in homogeneity indicates a more uniform distribution of pixel intensities, further emphasizing the smoothing effect of the treatment. These changes were statistically significant for each analyzed channel and the overall RGB images, reinforcing the efficacy of erbium glass laser therapy for acne scar management. When analyzing the individual RGB channels, distinct patterns emerged. The depth of light penetration varies across the channels of visible light, with blue light penetrating the shallowest and red light reaching the deepest layers of the skin [22]. The blue channel exhibited the most pronounced changes in contrast and significant changes in homogeneity, but not the largest increase among all channels. Its shallow penetration depth makes it particularly sensitive to surface-level textural changes, allowing it to capture subtle variations in skin surface irregularities. Additionally, the blue channel effectively highlights shallow discoloration changes, making it valuable for detecting subtle pigmentation irregularities. However, its sensitivity to surface-level changes may limit its ability to capture deeper textural alterations, which could reduce its utility for assessing treatments targeting subdermal structures. The higher baseline contrast in the blue channel might also make it more responsive to treatment-induced changes. The green channel also showed significant changes, which were comparable to or potentially exceeding those observed in the blue channel, depending on the specific parameter analyzed. The green channel is known for its balanced sensitivity to both vascular and structural components of the skin, making it a reliable indicator of textural improvements. The red channel displayed the smallest changes in both contrast and homogeneity. Its ability to penetrate deeper into the skin layers makes it less responsive to surface-level changes but valuable for assessing deeper structural alterations. This is consistent with findings from the study by [PERSON] et al., who demonstrated that larger laser spot sizes produce deeper thermal lesions while maintaining better epidermal integrity [23]. Although our study utilized a 70 um spot size, which is smaller than the maximum 140 um referenced in their research, it can be presumed that we primarily affected the superficial layers of the skin. Despite this, we still achieved significant efficacy in reducing acne scars. This suggests that the red channel's deeper penetration correlates with its role in identifying changes in deeper skin layers, which may not manifest as visibly pronounced surface-level improvements. The analysis of the combined RGB images integrates information from all three channels, providing a comprehensive overview of the treatment's impact on skin texture. The changes in contrast and homogeneity in these images--which reflect data derived from photographs without isolating individual color channels--further highlight the smoothing and unifying effects of the therapy. These findings emphasize that evaluating the RGB composite can offer a robust, holistic measure of treatment efficacy while ensuring that no significant detail is overlooked by isolating the channels.