Merge pull request #4 from eweidaw/master

Handle files from Lytro V2 format, by eweidaw, r=nrpatel

README

@@ -9,6 +9,10 @@ to process their files.
 This tool supports both the large raw files that come from the Lytro camera
 and the compressed files that the desktop software produces for web display.
 
+Note: The description below refers to .lfp file format for files generated
+using Lytro's Version 1 processing software. See README_V2 for a description
+of .lfp format changes as of Lytro's December 2012 update (Version 2).
+
 .lfp file format
 ----------------
 

README_V2

@@ -0,0 +1,65 @@
+In December 2012 Lytro released a software upgrade that supports
+perspective shift viewing and "living filters". This entailed a
+change to the contents of .lfp files as described below.
+================================================================
+
+The Lytro Version 2 software generates three .lfp files instead of two
+as in Version 1. These files are:
+
+  1. IMG_nnnn.lfp 
+
+     This file seems to be pretty much the same as Version 1. I have
+     not done a full analysis, however.
+
+  2. IMG_nnnn-dm.lfp
+
+     This file is new in Version 2. It contains an expanded depth
+     map (330 x 330) as well as a confidence map of the same
+     dimensions. I will wait for someone else to explain what
+     the confidence map is used for. The depth map represents
+     lambda values, as in Version 1, but at a much finer
+     granularity than in Version 1. 
+
+  3. IMG_nnnn-stk.lfp
+
+     A file with this name was also generated by Lytro Version 1 software,
+     but with the Version 2 format the contents have changed. The most
+     significant difference is that the image stacks are encoded as H264 frame
+     sequences. The -stk.lfp file may contain one or two image stacks (H264
+     frame sequences), depending on whether the user has performed
+     additional processing for shift perspective viewing using the
+     option provided in the Lytro processing software.
+
+An example of running the new lfpsplitter on Lytro files generated
+with Lytro's version 2 software is shown below. 
+
+$ ./lfpsplitter IMG_0008.lfp
+Saved IMG_0008_table.json
+Saved IMG_0008_imageRef0.raw
+Saved IMG_0008_metadataRef0.json
+Saved IMG_0008_privateMetadataRef1.json
+
+$ ./lfpsplitter IMG_0008-dm.lfp
+Saved IMG_0008-dm_table.json
+Saved IMG_0008-dm_lut_depth.txt
+Saved IMG_0008-dm_lut_confidence.txt
+
+$ ./lfpsplitter IMG_0008-stk.lfp 
+Saved IMG_0008-stk_table.json
+Saved IMG_0008-stk_blockOfImagesRef_00.h264
+Saved IMG_0008-stk_lut_depth.txt
+Saved IMG_0008-stk_blockOfImagesRef_01.h264
+
+The example shown above was run on an image where 
+perspective shift processing had been performed. If it
+had not been performed, only one .h264 file would
+have been output for IMG_0008-stk.lfp.
+
+Note tha lfpsplitter does NOT decode the H264 blocks into individual
+images. There are legal issues swirling around H264 decoding, so you
+will need to find another utility to accomplish this. You might
+try ffmpeg (ffmpeg.org). Using that utility, you could try the
+following command line to generate JPEGs:
+
+ffmpeg -format h265 -i IMG_0008-stk_blockOfImagesRef_00.h264 
+  -an -qscale 1 IMG_0008-stk_blockOfImagesRef_00_%04d.jpg

lfpsplitter.c

@@ -14,6 +14,9 @@
  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * Modifications for Lytro Version 2 files made on 1/13/2013 by
+ * Elissa Weidaw.
  */
 
 #include <stdio.h>
@@ -31,6 +34,8 @@ typedef unsigned int uint32_t;
 #define MAGIC_LENGTH 12
 #define BLANK_LENGTH 35
 #define STRING_LENGTH 256
+#define LUT_DIM_V1 20
+#define LUT_DIM_V2 330
 
 #ifdef _MSC_VER
 #define snprintf _snprintf
@@ -205,22 +210,35 @@ static void lfp_identify_section(lfp_file_p lfp, lfp_section_p section)
             strcpy(section->name, "unknown");
     }
 
-    // Hard coded to assume that the 20x20 LUT is 1600 bytes
-    if (section->len == 1600) {
+    // Test for Lytro Version 1 depth map
+    if (section->len == LUT_DIM_V1 * LUT_DIM_V1 * 4) {
         section->type = LFP_DEPTH_LUT;
         strcpy(section->name, "depth");
         return;
     }
 
+    // Test for Lytro Version 2 LUT (depth or confidence) map
+    if (section->len == LUT_DIM_V2 * LUT_DIM_V2 * 4) {
+        section->type = LFP_LUT;
+        strcpy(section->name, "lut");
+        return;
+    }
+
     // Check for the magic bytes to see if its a jpg
     if ((section->len > sizeof(jpeg)) && 
         (memcmp(section->data, jpeg, sizeof(jpeg)) == 0)) {
         section->type = LFP_JPEG;
         strcpy(section->name, "image");
         return;
     }
+
+    // Check for h264 block
+    if (strcmp(section->name, "blockOfImagesRef") == 0) {
+        section->type = LFP_BLOCK_OF_IMAGES;
+        return;
+    }
 
-    // Assume anything that isn't called imageRef is plain text json
+    // Assume anything else that isn't called imageRef is plain text json
     if (strcmp(section->name, "imageRef"))
         section->type = LFP_JSON;
 }
@@ -256,7 +274,7 @@ static void lfp_save_sections(lfp_file_p lfp)
 {
     char name[STRING_LENGTH];
     lfp_section_p section = lfp->sections;
-    int jpeg = 0, raw = 0, text = 0;
+    int jpeg = 0, raw = 0, text = 0, image_block = 0, lut = 0;
     char *buf;
     int buflen = 0;
 
@@ -293,12 +311,36 @@ static void lfp_save_sections(lfp_file_p lfp)
                     free(buf);
                 }
                 break;
+
+            // Lytro Version 2 LUT - depth or confidence map
+            case LFP_LUT:
+                // Parse the LUT and save as plaintext
+                buf = depth_string(section->data, &buflen, section->len);
+                if (buf) {
+                    if (lut++ == 0) {
+                        snprintf(name, STRING_LENGTH, "%s_%s_depth.txt", lfp->filename, section->name);
+                    } else {
+                        snprintf(name, STRING_LENGTH, "%s_%s_confidence.txt", lfp->filename, section->name);
+                    }
+                    if (save_data(buf, buflen, name)){
+                        printf("Saved %s\n", name);
+                    }
+                    free(buf);
+                }
+                break;
 
             case LFP_JPEG:
                 snprintf(name, STRING_LENGTH, "%s_%.2d.jpg", lfp->filename, jpeg++);
                 if (save_data(section->data, section->len, name))
                     printf("Saved %s\n", name);
                 break;
+
+            // Lytro Version 2 H264 block
+            case LFP_BLOCK_OF_IMAGES:
+                snprintf(name, STRING_LENGTH, "%s_%s_%.2d.h264", lfp->filename, section->name, image_block++);
+                if (save_data(section->data, section->len, name))
+                    printf("Saved %s\n", name);
+                break;
         }
 
         section = section->next;

lfpsplitter.h

@@ -5,7 +5,9 @@ typedef enum {
     LFP_RAW_IMAGE,
     LFP_JSON,
     LFP_DEPTH_LUT,
-    LFP_JPEG
+    LFP_LUT,
+    LFP_JPEG,
+    LFP_BLOCK_OF_IMAGES
 } section_type;
 
 typedef struct lfp_section {