diff options
Diffstat (limited to 'fiv-thumbnail.c')
| -rw-r--r-- | fiv-thumbnail.c | 494 |
1 files changed, 494 insertions, 0 deletions
diff --git a/fiv-thumbnail.c b/fiv-thumbnail.c new file mode 100644 index 0000000..1384213 --- /dev/null +++ b/fiv-thumbnail.c @@ -0,0 +1,494 @@ +// +// fiv-thumbnail.c: thumbnail management +// +// Copyright (c) 2021, Přemysl Eric Janouch <p@janouch.name> +// +// Permission to use, copy, modify, and/or distribute this software for any +// purpose with or without fee is hereby granted. +// +// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES +// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF +// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY +// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES +// 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. +// + +#include <spng.h> +#include <webp/encode.h> +#include <webp/mux.h> +#include <glib/gstdio.h> + +#include <math.h> +#include <stdbool.h> + +#include "fiv-io.h" +#include "fiv-thumbnail.h" +#include "xdg.h" + +#ifndef __linux__ +#define st_mtim st_mtimespec +#endif // ! __linux__ + +// TODO(p): Consider merging back with fiv-io. +#define FIV_THUMBNAIL_ERROR fiv_thumbnail_error_quark() + +G_DEFINE_QUARK(fiv-thumbnail-error-quark, fiv_thumbnail_error) + +enum FivThumbnailError { + FIV_THUMBNAIL_ERROR_IO +}; + +static void +set_error(GError **error, const char *message) +{ + g_set_error_literal( + error, FIV_THUMBNAIL_ERROR, FIV_THUMBNAIL_ERROR_IO, message); +} + +// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + +GType +fiv_thumbnail_size_get_type(void) +{ + static gsize guard; + if (g_once_init_enter(&guard)) { +#define XX(name, value, dir) {FIV_THUMBNAIL_SIZE_ ## name, \ + "FIV_THUMBNAIL_SIZE_" #name, #name}, + static const GEnumValue values[] = {FIV_THUMBNAIL_SIZES(XX) {}}; +#undef XX + GType type = g_enum_register_static( + g_intern_static_string("FivThumbnailSize"), values); + g_once_init_leave(&guard, type); + } + return guard; +} + +#define XX(name, value, dir) {value, dir}, +FivThumbnailSizeInfo + fiv_thumbnail_sizes[FIV_THUMBNAIL_SIZE_COUNT] = { + FIV_THUMBNAIL_SIZES(XX)}; +#undef XX + +// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + +cairo_user_data_key_t fiv_thumbnail_key_lq; + +static void +mark_thumbnail_lq(cairo_surface_t *surface) +{ + cairo_surface_set_user_data( + surface, &fiv_thumbnail_key_lq, (void *) (intptr_t) 1, NULL); +} + +gchar * +fiv_thumbnail_get_root(void) +{ + gchar *cache_dir = get_xdg_home_dir("XDG_CACHE_HOME", ".cache"); + gchar *thumbnails_dir = g_build_filename(cache_dir, "thumbnails", NULL); + g_free(cache_dir); + return thumbnails_dir; +} + +// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + +// In principle similar to rescale_thumbnail() from fiv-browser.c. +static cairo_surface_t * +rescale_thumbnail(cairo_surface_t *thumbnail, double row_height) +{ + cairo_format_t format = cairo_image_surface_get_format(thumbnail); + int width = cairo_image_surface_get_width(thumbnail); + int height = cairo_image_surface_get_height(thumbnail); + + double scale_x = 1; + double scale_y = 1; + if (width > FIV_THUMBNAIL_WIDE_COEFFICIENT * height) { + scale_x = FIV_THUMBNAIL_WIDE_COEFFICIENT * row_height / width; + scale_y = round(scale_x * height) / height; + } else { + scale_y = row_height / height; + scale_x = round(scale_y * width) / width; + } + if (scale_x == 1 && scale_y == 1) + return cairo_surface_reference(thumbnail); + + int projected_width = round(scale_x * width); + int projected_height = round(scale_y * height); + cairo_surface_t *scaled = cairo_image_surface_create( + (format == CAIRO_FORMAT_RGB24 || format == CAIRO_FORMAT_RGB30) + ? CAIRO_FORMAT_RGB24 + : CAIRO_FORMAT_ARGB32, + projected_width, projected_height); + + cairo_t *cr = cairo_create(scaled); + cairo_scale(cr, scale_x, scale_y); + + cairo_set_source_surface(cr, thumbnail, 0, 0); + cairo_pattern_t *pattern = cairo_get_source(cr); + cairo_pattern_set_filter(pattern, CAIRO_FILTER_BEST); + cairo_pattern_set_extend(pattern, CAIRO_EXTEND_PAD); + + cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE); + cairo_paint(cr); + cairo_destroy(cr); + mark_thumbnail_lq(scaled); + return scaled; +} + +static WebPData +encode_thumbnail(cairo_surface_t *surface) +{ + WebPData bitstream = {}; + WebPConfig config = {}; + if (!WebPConfigInit(&config) || !WebPConfigLosslessPreset(&config, 6)) + return bitstream; + + config.near_lossless = 95; + config.thread_level = true; + if (!WebPValidateConfig(&config)) + return bitstream; + + bitstream.bytes = fiv_io_encode_webp(surface, &config, &bitstream.size); + return bitstream; +} + +static void +save_thumbnail(cairo_surface_t *thumbnail, const char *path, GString *thum) +{ + WebPMux *mux = WebPMuxNew(); + WebPData bitstream = encode_thumbnail(thumbnail); + gboolean ok = WebPMuxSetImage(mux, &bitstream, true) == WEBP_MUX_OK; + WebPDataClear(&bitstream); + + WebPData data = {.bytes = (const uint8_t *) thum->str, .size = thum->len}; + ok = ok && WebPMuxSetChunk(mux, "THUM", &data, false) == WEBP_MUX_OK; + + WebPData assembled = {}; + WebPDataInit(&assembled); + ok = ok && WebPMuxAssemble(mux, &assembled) == WEBP_MUX_OK; + WebPMuxDelete(mux); + if (!ok) { + g_warning("thumbnail encoding failed"); + return; + } + + GError *e = NULL; + while (!g_file_set_contents( + path, (const gchar *) assembled.bytes, assembled.size, &e)) { + bool missing_parents = + e->domain == G_FILE_ERROR && e->code == G_FILE_ERROR_NOENT; + g_debug("%s: %s", path, e->message); + g_clear_error(&e); + if (!missing_parents) + break; + + gchar *dirname = g_path_get_dirname(path); + int err = g_mkdir_with_parents(dirname, 0755); + if (err) + g_debug("%s: %s", dirname, g_strerror(errno)); + + g_free(dirname); + if (err) + break; + } + + // It would be possible to create square thumbnails as well, + // but it seems like wasted effort. + WebPDataClear(&assembled); +} + +gboolean +fiv_thumbnail_produce(GFile *target, FivThumbnailSize max_size, GError **error) +{ + g_return_val_if_fail(max_size >= FIV_THUMBNAIL_SIZE_MIN && + max_size <= FIV_THUMBNAIL_SIZE_MAX, FALSE); + + // Local files only, at least for now. + gchar *path = g_file_get_path(target); + if (!path) + return FALSE; + + GMappedFile *mf = g_mapped_file_new(path, FALSE, error); + if (!mf) { + g_free(path); + return FALSE; + } + + GStatBuf st = {}; + if (g_stat(path, &st)) { + set_error(error, g_strerror(errno)); + g_free(path); + return FALSE; + } + + // TODO(p): Add a flag to avoid loading all pages and frames. + FivIoProfile sRGB = fiv_io_profile_new_sRGB(); + gsize filesize = g_mapped_file_get_length(mf); + cairo_surface_t *surface = fiv_io_open_from_data( + g_mapped_file_get_contents(mf), filesize, path, sRGB, FALSE, error); + + g_free(path); + g_mapped_file_unref(mf); + if (sRGB) + fiv_io_profile_free(sRGB); + if (!surface) + return FALSE; + + // Boilerplate copied from fiv_thumbnail_lookup(). + gchar *uri = g_file_get_uri(target); + gchar *sum = g_compute_checksum_for_string(G_CHECKSUM_MD5, uri, -1); + gchar *thumbnails_dir = fiv_thumbnail_get_root(); + + GString *thum = g_string_new(""); + g_string_append_printf( + thum, "%s%c%s%c", "Thumb::URI", 0, uri, 0); + g_string_append_printf( + thum, "%s%c%ld%c", "Thumb::Mtime", 0, (long) st.st_mtim.tv_sec, 0); + g_string_append_printf( + thum, "%s%c%ld%c", "Thumb::Size", 0, (long) filesize, 0); + g_string_append_printf(thum, "%s%c%d%c", "Thumb::Image::Width", 0, + cairo_image_surface_get_width(surface), 0); + g_string_append_printf(thum, "%s%c%d%c", "Thumb::Image::Height", 0, + cairo_image_surface_get_height(surface), 0); + + // Without a CMM, no conversion is attempted. + if (sRGB) { + g_string_append_printf( + thum, "%s%c%s%c", "Thumb::ColorSpace", 0, "sRGB", 0); + } + + for (int use = max_size; use >= FIV_THUMBNAIL_SIZE_MIN; use--) { + cairo_surface_t *scaled = + rescale_thumbnail(surface, fiv_thumbnail_sizes[use].size); + gchar *path = g_strdup_printf("%s/wide-%s/%s.webp", thumbnails_dir, + fiv_thumbnail_sizes[use].thumbnail_spec_name, sum); + save_thumbnail(scaled, path, thum); + cairo_surface_destroy(scaled); + g_free(path); + } + + g_string_free(thum, TRUE); + + g_free(thumbnails_dir); + g_free(sum); + g_free(uri); + cairo_surface_destroy(surface); + return TRUE; +} + +static cairo_surface_t * +read_wide_thumbnail( + const gchar *path, const gchar *uri, time_t mtime, GError **error) +{ + // TODO(p): Validate fiv_io_key_thum. + (void) uri; + (void) mtime; + return fiv_io_open(path, NULL, FALSE, error); +} + +// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + +static int // tri-state +check_spng_thumbnail_texts(struct spng_text *texts, uint32_t texts_len, + const gchar *target, time_t mtime) +{ + // May contain Thumb::Image::Width Thumb::Image::Height, + // but those aren't interesting currently (would be for fast previews). + bool need_uri = true, need_mtime = true; + for (uint32_t i = 0; i < texts_len; i++) { + struct spng_text *text = texts + i; + if (!strcmp(text->keyword, "Thumb::URI")) { + need_uri = false; + if (strcmp(target, text->text)) + return false; + } + if (!strcmp(text->keyword, "Thumb::MTime")) { + need_mtime = false; + if (atol(text->text) != mtime) + return false; + } + } + return need_uri || need_mtime ? -1 : true; +} + +static int // tri-state +check_spng_thumbnail(spng_ctx *ctx, const gchar *target, time_t mtime, int *err) +{ + uint32_t texts_len = 0; + if ((*err = spng_get_text(ctx, NULL, &texts_len))) + return false; + + int result = false; + struct spng_text *texts = g_malloc0_n(texts_len, sizeof *texts); + if (!(*err = spng_get_text(ctx, texts, &texts_len))) + result = check_spng_thumbnail_texts(texts, texts_len, target, mtime); + g_free(texts); + return result; +} + +static cairo_surface_t * +read_spng_thumbnail( + const gchar *path, const gchar *uri, time_t mtime, GError **error) +{ + FILE *fp; + cairo_surface_t *result = NULL; + if (!(fp = fopen(path, "rb"))) { + set_error(error, g_strerror(errno)); + return NULL; + } + + errno = 0; + spng_ctx *ctx = spng_ctx_new(0); + if (!ctx) { + set_error(error, g_strerror(errno)); + goto fail_init; + } + + int err; + size_t size = 0; + if ((err = spng_set_png_file(ctx, fp)) || + (err = spng_set_image_limits(ctx, INT16_MAX, INT16_MAX)) || + (err = spng_decoded_image_size(ctx, SPNG_FMT_RGBA8, &size))) { + set_error(error, spng_strerror(err)); + goto fail; + } + if (check_spng_thumbnail(ctx, uri, mtime, &err) == false) { + set_error(error, err ? spng_strerror(err) : "mismatch"); + goto fail; + } + + struct spng_ihdr ihdr = {}; + struct spng_trns trns = {}; + spng_get_ihdr(ctx, &ihdr); + bool may_be_translucent = !spng_get_trns(ctx, &trns) || + ihdr.color_type == SPNG_COLOR_TYPE_GRAYSCALE_ALPHA || + ihdr.color_type == SPNG_COLOR_TYPE_TRUECOLOR_ALPHA; + + cairo_surface_t *surface = cairo_image_surface_create( + may_be_translucent ? CAIRO_FORMAT_ARGB32 : CAIRO_FORMAT_RGB24, + ihdr.width, ihdr.height); + + cairo_status_t surface_status = cairo_surface_status(surface); + if (surface_status != CAIRO_STATUS_SUCCESS) { + set_error(error, cairo_status_to_string(surface_status)); + goto fail_data; + } + + uint32_t *data = (uint32_t *) cairo_image_surface_get_data(surface); + g_assert((size_t) cairo_image_surface_get_stride(surface) * + cairo_image_surface_get_height(surface) == size); + + cairo_surface_flush(surface); + if ((err = spng_decode_image(ctx, data, size, SPNG_FMT_RGBA8, + SPNG_DECODE_TRNS | SPNG_DECODE_GAMMA))) { + set_error(error, spng_strerror(err)); + goto fail_data; + } + + // The specification does not say where the required metadata should be, + // it could very well be broken up into two parts. + if (check_spng_thumbnail(ctx, uri, mtime, &err) != true) { + set_error( + error, err ? spng_strerror(err) : "mismatch or not a thumbnail"); + goto fail_data; + } + + // pixman can be mildly abused to do this operation, but it won't be faster. + if (may_be_translucent) { + for (size_t i = size / sizeof *data; i--; ) { + const uint8_t *unit = (const uint8_t *) &data[i]; + uint32_t a = unit[3], + b = PREMULTIPLY8(a, unit[2]), + g = PREMULTIPLY8(a, unit[1]), + r = PREMULTIPLY8(a, unit[0]); + data[i] = a << 24 | r << 16 | g << 8 | b; + } + } else { + for (size_t i = size / sizeof *data; i--; ) { + uint32_t rgba = g_ntohl(data[i]); + data[i] = rgba << 24 | rgba >> 8; + } + } + + cairo_surface_mark_dirty((result = surface)); + +fail_data: + if (!result) + cairo_surface_destroy(surface); +fail: + spng_ctx_free(ctx); +fail_init: + fclose(fp); + return result; +} + +cairo_surface_t * +fiv_thumbnail_lookup(GFile *target, FivThumbnailSize size) +{ + g_return_val_if_fail(size >= FIV_THUMBNAIL_SIZE_MIN && + size <= FIV_THUMBNAIL_SIZE_MAX, NULL); + + // Local files only, at least for now. + gchar *path = g_file_get_path(target); + if (!path) + return NULL; + + GStatBuf st = {}; + int err = g_stat(path, &st); + g_free(path); + if (err) + return NULL; + + gchar *uri = g_file_get_uri(target); + gchar *sum = g_compute_checksum_for_string(G_CHECKSUM_MD5, uri, -1); + gchar *thumbnails_dir = fiv_thumbnail_get_root(); + + // The lookup sequence is: nominal..max, then mirroring back to ..min. + cairo_surface_t *result = NULL; + GError *error = NULL; + for (int i = 0; i < FIV_THUMBNAIL_SIZE_COUNT; i++) { + FivThumbnailSize use = size + i; + if (use > FIV_THUMBNAIL_SIZE_MAX) + use = FIV_THUMBNAIL_SIZE_MAX - i; + + const char *name = fiv_thumbnail_sizes[use].thumbnail_spec_name; + gchar *wide = + g_strdup_printf("%s/wide-%s/%s.webp", thumbnails_dir, name, sum); + result = read_wide_thumbnail(wide, uri, st.st_mtim.tv_sec, &error); + if (error) { + g_debug("%s: %s", wide, error->message); + g_clear_error(&error); + } + g_free(wide); + if (result) { + // Higher up we can't distinguish images smaller than the thumbnail. + // Also, try not to rescale the already rescaled. + if (use != size) + mark_thumbnail_lq(result); + break; + } + + gchar *path = + g_strdup_printf("%s/%s/%s.png", thumbnails_dir, name, sum); + result = read_spng_thumbnail(path, uri, st.st_mtim.tv_sec, &error); + if (error) { + g_debug("%s: %s", path, error->message); + g_clear_error(&error); + } + g_free(path); + if (result) { + // Whatever produced it, we may be able to outclass it. + mark_thumbnail_lq(result); + break; + } + } + + // TODO(p): We can definitely extract embedded thumbnails, but it should be + // done as a separate stage--the file may be stored on a slow device. + + g_free(thumbnails_dir); + g_free(sum); + g_free(uri); + return result; +} |