Add looping Ogg Opus [Monster Boy and the Cursed Kingdom (Switch)]

src/formats.c

@@ -1123,6 +1123,7 @@ static const meta_info meta_info_list[] = {
         {meta_XPS_DAT,              "From Software .XPS+DAT header"},
         {meta_ZSND,                 "Vicarious Visions ZSND header"},
         {meta_DSP_ADPCMX,           "AQUASTYLE ADPY header"},
+        {meta_OGG_OPUS,             "Ogg Opus header"},
 
 };
 

src/libvgmstream.vcproj

@@ -865,6 +865,10 @@
                 <File
                     RelativePath=".\meta\nxap.c"
                     >
+                </File>
+                <File
+                    RelativePath=".\meta\ogg_opus.c"
+                    >
                 </File>
 				<File
 					RelativePath=".\meta\ogg_vorbis.c"

src/libvgmstream.vcxproj

@@ -324,6 +324,7 @@
     <ClCompile Include="meta\nwav.c" />
     <ClCompile Include="meta\nxa.c" />
     <ClCompile Include="meta\nxap.c" />
+    <ClCompile Include="meta\ogg_opus.c" />
     <ClCompile Include="meta\ogg_vorbis.c" />
     <ClCompile Include="meta\ogl.c" />
     <ClCompile Include="meta\omu.c" />

src/libvgmstream.vcxproj.filters

@@ -535,6 +535,9 @@
     <ClCompile Include="meta\nxap.c">
       <Filter>meta\Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="meta\ogg_opus.c">
+      <Filter>meta\Source Files</Filter>
+    </ClCompile>
     <ClCompile Include="meta\ogg_vorbis.c">
       <Filter>meta\Source Files</Filter>
     </ClCompile>

src/meta/meta.h

@@ -817,4 +817,6 @@ VGMSTREAM * init_vgmstream_xps(STREAMFILE * streamFile);
 
 VGMSTREAM * init_vgmstream_zsnd(STREAMFILE * streamFile);
 
+VGMSTREAM * init_vgmstream_ogg_opus(STREAMFILE * streamFile);
+
 #endif /*_META_H*/

src/meta/ogg_opus.c

@@ -0,0 +1,173 @@
+#include "meta.h"
+#include "../coding/coding.h"
+
+
+static int get_ogg_page_size(STREAMFILE *streamFile, off_t page_offset, off_t *out_data_offset, size_t *out_page_size);
+static int ogg_get_num_samples(STREAMFILE *streamFile, off_t start_offset);
+
+/* Ogg Opus - standard Opus with optional looping comments [The Pillars of Earth (PC), Monster Boy and the Cursed Kingdom (Switch)] */
+VGMSTREAM * init_vgmstream_ogg_opus(STREAMFILE *streamFile) {
+    VGMSTREAM * vgmstream = NULL;
+    off_t start_offset, data_offset = 0;
+    size_t page_size = 0;
+    int loop_flag, channel_count, original_rate;
+    int loop_start = 0, loop_end = 0;
+
+
+    /* checks */
+    /* .opus: standard, .lopus: fake extension for plugins
+     * .ogg: less common, .logg: same */
+    if (!check_extensions(streamFile, "opus,lopus,ogg,logg"))
+        goto fail;
+    if (read_32bitBE(0x00,streamFile) != 0x4F676753) /* "OggS" */
+        goto fail;
+    /* see: https://tools.ietf.org/html/rfc7845.html */
+
+    start_offset = 0x00;
+
+    /* parse 1st page: opus head */
+    if (!get_ogg_page_size(streamFile, start_offset, &data_offset, &page_size))
+        goto fail;
+    if (read_32bitBE(data_offset+0x00,streamFile) != 0x4F707573 &&  /* "Opus" */
+        read_32bitBE(data_offset+0x04,streamFile) != 0x48656164)    /* "Head" */
+        goto fail;
+    /* 0x01: version 1, fixed */
+    channel_count = read_8bit(data_offset+0x09,streamFile);
+    /* 0x0A: skip samples */
+    original_rate = read_32bitLE(data_offset+0x0c,streamFile);
+    /* 0x10: gain */
+    /* 0x12: mapping family */
+
+    /* parse 2nd page: opus tags (also mandatory) */
+    if (!get_ogg_page_size(streamFile, start_offset+page_size, &data_offset, &page_size))
+        goto fail;
+    if (read_32bitBE(data_offset+0x00,streamFile) != 0x4F707573 &&  /* "Opus" */
+        read_32bitBE(data_offset+0x04,streamFile) != 0x54616773)    /* "Tags" */
+        goto fail;
+
+    loop_flag = 0;
+    {
+        char user_comment[1024+1];
+        off_t offset;
+        int vendor_size, comment_count, user_comment_size, user_comment_max;
+        int i;
+        int has_encoder_options = 0, has_title = 0;
+
+        vendor_size   = read_32bitLE(data_offset+0x08,streamFile);
+        comment_count = read_32bitLE(data_offset+0x0c+vendor_size,streamFile);
+
+        /* parse comments */
+        offset = data_offset + 0x0c + vendor_size + 0x04;
+        for (i = 0; i < comment_count; i++) {
+            user_comment_size = read_32bitLE(offset+0x00,streamFile);
+            user_comment_max = user_comment_size > 1024 ? 1024 : user_comment_size;
+            read_string(user_comment,user_comment_max+1, offset+0x04,streamFile);
+
+
+            /* parse loop strings */
+            if (strstr(user_comment,"LOOP_START=")==user_comment) { /* Monster Boy and the Cursed Kingdom (Switch) */
+                loop_start = atol(strrchr(user_comment,'=')+1);
+                loop_flag = (loop_start >= 0);
+            }
+            else if (strstr(user_comment,"LOOP_END=")==user_comment) { /* LOOP_START pair */
+                loop_end = atol(strrchr(user_comment,'=')+1);
+            }
+            else if (strstr(user_comment,"ENCODER_OPTIONS=")==user_comment) { /* for detection */
+                has_encoder_options = 1;
+            }
+            else if (strstr(user_comment,"TITLE=")==user_comment) { /* for detection */
+                has_title = 1;
+            }
+
+
+            //;VGM_LOG("OggOpus: user_comment=%s\n", user_comment);
+            offset += 0x04 + user_comment_size;
+        }
+
+
+        /* Monster Boy has loop points for 44100hz (what), but Opus is resampled so
+         * they must be adjusted (with extra checks just in case). */
+        if (loop_flag && original_rate < 48000 && has_encoder_options && has_title) {
+            float modifier = 48000.0f / (float)original_rate;
+            loop_start = loop_start * modifier;
+            loop_end = loop_end * modifier;
+        }
+    }
+
+
+    /* build the VGMSTREAM */
+    vgmstream = allocate_vgmstream(channel_count, loop_flag);
+    if (!vgmstream) goto fail;
+
+    vgmstream->meta_type = meta_OGG_OPUS;
+    vgmstream->sample_rate = 48000; /* Opus always resamples to this */
+    vgmstream->num_samples = ogg_get_num_samples(streamFile, 0x00);
+    vgmstream->loop_start_sample = loop_start;
+    vgmstream->loop_end_sample = loop_end;
+
+#ifdef VGM_USE_FFMPEG
+    {
+        vgmstream->codec_data = init_ffmpeg_offset(streamFile, start_offset, get_streamfile_size(streamFile));
+        if (!vgmstream->codec_data) goto fail;
+        vgmstream->coding_type = coding_FFmpeg;
+        vgmstream->layout_type = layout_none;
+        /* FFmpeg+libopus handles skip samples ok, FFmpeg+opus doesn't */
+    }
+#else
+    goto fail;
+#endif
+    
+    if (!vgmstream_open_stream(vgmstream,streamFile,start_offset))
+        goto fail;
+    return vgmstream;
+
+fail:
+    close_vgmstream(vgmstream);
+    return NULL;
+}
+
+
+/* parse OggS's bizarre segment table */
+static int get_ogg_page_size(STREAMFILE *streamFile, off_t page_offset, off_t *out_data_offset, size_t *out_page_size) {
+    uint8_t segments;
+    size_t page_size = 0;
+    int i;
+
+    if (read_32bitBE(page_offset+0x00,streamFile) != 0x4F676753) /* "OggS" */
+        goto fail;
+
+    /* read all segment sizes */
+    segments = (uint8_t)read_8bit(page_offset+0x1a, streamFile);
+    for (i = 0; i < segments; i++) {
+        page_size += (uint8_t)read_8bit(page_offset + 0x1b + i, streamFile);
+    }
+    page_size += 0x1b + segments;
+
+    if (out_data_offset) *out_data_offset = page_offset + 0x1b + segments;
+    if (out_page_size) *out_page_size = page_size;
+    return 1;
+fail:
+    return 0;
+}
+
+/* Ogg doesn't have num_samples info, must manually seek+read last granule
+ * (Xiph is insistent this is the One True Way). */
+static int ogg_get_num_samples(STREAMFILE *streamFile, off_t start_offset) {
+    uint32_t expected_id = 0x4F676753;
+    off_t offset = get_streamfile_size(streamFile) - 0x04-0x01-0x01-0x08-0x04-0x04-0x04;
+
+    //todo better buffer reads (Ogg page max is 0xFFFF)
+    //lame way to force buffer, assuming it's around that
+    read_32bitBE(offset - 0x4000, streamFile);
+
+    while (offset >= start_offset) {
+        uint32_t current_id = read_32bitBE(offset, streamFile);
+        if (current_id == expected_id) { /* if more checks are needed last page starts with 0x0004 */
+            return read_32bitLE(offset+0x04+0x01+0x01, streamFile); /* get last granule = total samples (64b but whatevs) */
+        }
+
+        offset--;
+    }
+
+    return 0;
+}

src/vgmstream.c

@@ -455,6 +455,7 @@ VGMSTREAM * (*init_vgmstream_functions[])(STREAMFILE *streamFile) = {
     init_vgmstream_zsnd,
     init_vgmstream_opus_opusx,
     init_vgmstream_dsp_adpcmx,
+    init_vgmstream_ogg_opus,
 
     /* lowest priority metas (should go after all metas, and TXTH should go before raw formats) */
     init_vgmstream_txth,            /* proper parsers should supersede TXTH, once added */

src/vgmstream.h

@@ -708,7 +708,8 @@ typedef enum {
     meta_MSF_TAMASOFT,
     meta_XPS_DAT,
     meta_ZSND,
-    meta_DSP_ADPCMX
+    meta_DSP_ADPCMX,
+    meta_OGG_OPUS
 
 } meta_t;