/* save to jpeg
 *
 * 24/11/11
 * 	- wrap a class around the jpeg writer
 * 18/2/20 Elad-Laufer
 * 	- add subsample_mode, deprecate no_subsample
 */

/*

	This file is part of VIPS.

	VIPS is free software; you can redistribute it and/or modify
	it under the terms of the GNU Lesser General Public License as published by
	the Free Software Foundation; either version 2 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU Lesser General Public License for more details.

	You should have received a copy of the GNU Lesser General Public License
	along with this program; if not, write to the Free Software
	Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
	02110-1301  USA

 */

/*

	These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk

 */

/*
#define DEBUG_VERBOSE
#define DEBUG
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /*HAVE_CONFIG_H*/
#include <glib/gi18n-lib.h>

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <setjmp.h>

#include <vips/vips.h>
#include <vips/buf.h>
#include <vips/internal.h>

#include "pforeign.h"

#ifdef HAVE_JPEG

typedef struct _VipsForeignSaveJpeg {
	VipsForeignSave parent_object;

	/* Quality factor.
	 */
	int Q;

	/* Compute optimal Huffman coding tables.
	 */
	gboolean optimize_coding;

	/* Generate an interlaced (progressive, in jpg terminology) file.
	 */
	gboolean interlace;

	/* Deprecated: Disable chroma subsampling. Use subsample_mode instead.
	 */
	gboolean no_subsample;

	/* Select chroma subsampling mode:
	 * auto will disable subsampling for Q >= 90
	 * on will always enable subsampling
	 * off will always disable subsampling
	 */
	VipsForeignSubsample subsample_mode;

	/* Apply trellis quantisation to each 8x8 block.
	 */
	gboolean trellis_quant;

	/* Apply overshooting to samples with extreme values e.g. 0 & 255
	 * for 8-bit.
	 */
	gboolean overshoot_deringing;

	/* Split the spectrum of DCT coefficients into separate scans.
	 */
	gboolean optimize_scans;

	/* Use predefined quantization table with given index.
	 */
	int quant_table;

	/* Use an MCU restart interval.
	 */
	int restart_interval;

} VipsForeignSaveJpeg;

typedef VipsForeignSaveClass VipsForeignSaveJpegClass;

G_DEFINE_ABSTRACT_TYPE(VipsForeignSaveJpeg, vips_foreign_save_jpeg,
	VIPS_TYPE_FOREIGN_SAVE);

#define UC VIPS_FORMAT_UCHAR

/* Type promotion for save ... just always go to uchar.
 */
static VipsBandFormat bandfmt_jpeg[10] = {
	/* Band format:  UC  C   US  S   UI  I   F   X   D   DX */
	/* Promotion: */ UC, UC, UC, UC, UC, UC, UC, UC, UC, UC
};

static int
vips_foreign_save_jpeg_build(VipsObject *object)
{
	VipsForeignSaveJpeg *jpeg = (VipsForeignSaveJpeg *) object;

	if (VIPS_OBJECT_CLASS(vips_foreign_save_jpeg_parent_class)->build(object))
		return -1;

	/* no_subsample is deprecated, but we retain backwards compatibility
	 * new code should use subsample_mode
	 */
	if (vips_object_argument_isset(object, "no_subsample"))
		jpeg->subsample_mode = jpeg->no_subsample
			? VIPS_FOREIGN_SUBSAMPLE_OFF
			: VIPS_FOREIGN_SUBSAMPLE_AUTO;

	return 0;
}

static void
vips_foreign_save_jpeg_class_init(VipsForeignSaveJpegClass *class)
{
	GObjectClass *gobject_class = G_OBJECT_CLASS(class);
	VipsObjectClass *object_class = (VipsObjectClass *) class;
	VipsForeignClass *foreign_class = (VipsForeignClass *) class;
	VipsForeignSaveClass *save_class = (VipsForeignSaveClass *) class;

	gobject_class->set_property = vips_object_set_property;
	gobject_class->get_property = vips_object_get_property;

	object_class->nickname = "jpegsave_base";
	object_class->description = _("save jpeg");
	object_class->build = vips_foreign_save_jpeg_build;

	foreign_class->suffs = vips__jpeg_suffs;

	/* See also vips_foreign_save_tiff_build() when saving JPEG in TIFF.
	 */
	save_class->saveable = VIPS_SAVEABLE_RGB_CMYK;
	save_class->format_table = bandfmt_jpeg;

	VIPS_ARG_INT(class, "Q", 10,
		_("Q"),
		_("Q factor"),
		VIPS_ARGUMENT_OPTIONAL_INPUT,
		G_STRUCT_OFFSET(VipsForeignSaveJpeg, Q),
		1, 100, 75);

	VIPS_ARG_BOOL(class, "optimize_coding", 12,
		_("Optimize coding"),
		_("Compute optimal Huffman coding tables"),
		VIPS_ARGUMENT_OPTIONAL_INPUT,
		G_STRUCT_OFFSET(VipsForeignSaveJpeg, optimize_coding),
		FALSE);

	VIPS_ARG_BOOL(class, "interlace", 13,
		_("Interlace"),
		_("Generate an interlaced (progressive) jpeg"),
		VIPS_ARGUMENT_OPTIONAL_INPUT,
		G_STRUCT_OFFSET(VipsForeignSaveJpeg, interlace),
		FALSE);

	VIPS_ARG_BOOL(class, "no_subsample", 14,
		_("No subsample"),
		_("Disable chroma subsample"),
		VIPS_ARGUMENT_OPTIONAL_INPUT | VIPS_ARGUMENT_DEPRECATED,
		G_STRUCT_OFFSET(VipsForeignSaveJpeg, no_subsample),
		FALSE);

	VIPS_ARG_BOOL(class, "trellis_quant", 15,
		_("Trellis quantisation"),
		_("Apply trellis quantisation to each 8x8 block"),
		VIPS_ARGUMENT_OPTIONAL_INPUT,
		G_STRUCT_OFFSET(VipsForeignSaveJpeg, trellis_quant),
		FALSE);

	VIPS_ARG_BOOL(class, "overshoot_deringing", 16,
		_("Overshoot de-ringing"),
		_("Apply overshooting to samples with extreme values"),
		VIPS_ARGUMENT_OPTIONAL_INPUT,
		G_STRUCT_OFFSET(VipsForeignSaveJpeg, overshoot_deringing),
		FALSE);

	VIPS_ARG_BOOL(class, "optimize_scans", 17,
		_("Optimize scans"),
		_("Split spectrum of DCT coefficients into separate scans"),
		VIPS_ARGUMENT_OPTIONAL_INPUT,
		G_STRUCT_OFFSET(VipsForeignSaveJpeg, optimize_scans),
		FALSE);

	VIPS_ARG_INT(class, "quant_table", 18,
		_("Quantization table"),
		_("Use predefined quantization table with given index"),
		VIPS_ARGUMENT_OPTIONAL_INPUT,
		G_STRUCT_OFFSET(VipsForeignSaveJpeg, quant_table),
		0, 8, 0);

	VIPS_ARG_ENUM(class, "subsample_mode", 19,
		_("Subsample mode"),
		_("Select chroma subsample operation mode"),
		VIPS_ARGUMENT_OPTIONAL_INPUT,
		G_STRUCT_OFFSET(VipsForeignSaveJpeg, subsample_mode),
		VIPS_TYPE_FOREIGN_SUBSAMPLE,
		VIPS_FOREIGN_SUBSAMPLE_AUTO);

	VIPS_ARG_INT(class, "restart_interval", 20,
		_("Restart interval"),
		_("Add restart markers every specified number of mcu"),
		VIPS_ARGUMENT_OPTIONAL_INPUT,
		G_STRUCT_OFFSET(VipsForeignSaveJpeg, restart_interval),
		0, INT_MAX, 0);
}

static void
vips_foreign_save_jpeg_init(VipsForeignSaveJpeg *jpeg)
{
	jpeg->Q = 75;
	jpeg->subsample_mode = VIPS_FOREIGN_SUBSAMPLE_AUTO;
}

typedef struct _VipsForeignSaveJpegTarget {
	VipsForeignSaveJpeg parent_object;

	VipsTarget *target;

} VipsForeignSaveJpegTarget;

typedef VipsForeignSaveJpegClass VipsForeignSaveJpegTargetClass;

G_DEFINE_TYPE(VipsForeignSaveJpegTarget, vips_foreign_save_jpeg_target,
	vips_foreign_save_jpeg_get_type());

static int
vips_foreign_save_jpeg_target_build(VipsObject *object)
{
	VipsForeignSave *save = (VipsForeignSave *) object;
	VipsForeignSaveJpeg *jpeg = (VipsForeignSaveJpeg *) object;
	VipsForeignSaveJpegTarget *target =
		(VipsForeignSaveJpegTarget *) object;

	if (VIPS_OBJECT_CLASS(vips_foreign_save_jpeg_target_parent_class)
			->build(object))
		return -1;

	if (vips__jpeg_write_target(save->ready, target->target,
			jpeg->Q, save->profile, jpeg->optimize_coding,
			jpeg->interlace,
			jpeg->trellis_quant, jpeg->overshoot_deringing,
			jpeg->optimize_scans, jpeg->quant_table,
			jpeg->subsample_mode, jpeg->restart_interval))
		return -1;

	return 0;
}

static void
vips_foreign_save_jpeg_target_class_init(
	VipsForeignSaveJpegTargetClass *class)
{
	GObjectClass *gobject_class = G_OBJECT_CLASS(class);
	VipsObjectClass *object_class = (VipsObjectClass *) class;

	gobject_class->set_property = vips_object_set_property;
	gobject_class->get_property = vips_object_get_property;

	object_class->nickname = "jpegsave_target";
	object_class->description = _("save image to jpeg target");
	object_class->build = vips_foreign_save_jpeg_target_build;

	VIPS_ARG_OBJECT(class, "target", 1,
		_("Target"),
		_("Target to save to"),
		VIPS_ARGUMENT_REQUIRED_INPUT,
		G_STRUCT_OFFSET(VipsForeignSaveJpegTarget, target),
		VIPS_TYPE_TARGET);
}

static void
vips_foreign_save_jpeg_target_init(VipsForeignSaveJpegTarget *target)
{
}

typedef struct _VipsForeignSaveJpegFile {
	VipsForeignSaveJpeg parent_object;

	/* Filename for save.
	 */
	char *filename;

} VipsForeignSaveJpegFile;

typedef VipsForeignSaveJpegClass VipsForeignSaveJpegFileClass;

G_DEFINE_TYPE(VipsForeignSaveJpegFile, vips_foreign_save_jpeg_file,
	vips_foreign_save_jpeg_get_type());

static int
vips_foreign_save_jpeg_file_build(VipsObject *object)
{
	VipsForeignSave *save = (VipsForeignSave *) object;
	VipsForeignSaveJpeg *jpeg = (VipsForeignSaveJpeg *) object;
	VipsForeignSaveJpegFile *file = (VipsForeignSaveJpegFile *) object;

	VipsTarget *target;

	if (VIPS_OBJECT_CLASS(vips_foreign_save_jpeg_file_parent_class)
			->build(object))
		return -1;

	if (!(target = vips_target_new_to_file(file->filename)))
		return -1;
	if (vips__jpeg_write_target(save->ready, target,
			jpeg->Q, save->profile, jpeg->optimize_coding,
			jpeg->interlace,
			jpeg->trellis_quant, jpeg->overshoot_deringing,
			jpeg->optimize_scans, jpeg->quant_table,
			jpeg->subsample_mode, jpeg->restart_interval)) {
		VIPS_UNREF(target);
		return -1;
	}
	VIPS_UNREF(target);

	return 0;
}

static void
vips_foreign_save_jpeg_file_class_init(VipsForeignSaveJpegFileClass *class)
{
	GObjectClass *gobject_class = G_OBJECT_CLASS(class);
	VipsObjectClass *object_class = (VipsObjectClass *) class;

	gobject_class->set_property = vips_object_set_property;
	gobject_class->get_property = vips_object_get_property;

	object_class->nickname = "jpegsave";
	object_class->description = _("save image to jpeg file");
	object_class->build = vips_foreign_save_jpeg_file_build;

	VIPS_ARG_STRING(class, "filename", 1,
		_("Filename"),
		_("Filename to save to"),
		VIPS_ARGUMENT_REQUIRED_INPUT,
		G_STRUCT_OFFSET(VipsForeignSaveJpegFile, filename),
		NULL);
}

static void
vips_foreign_save_jpeg_file_init(VipsForeignSaveJpegFile *file)
{
}

typedef struct _VipsForeignSaveJpegBuffer {
	VipsForeignSaveJpeg parent_object;

	/* Save to a buffer.
	 */
	VipsArea *buf;

} VipsForeignSaveJpegBuffer;

typedef VipsForeignSaveJpegClass VipsForeignSaveJpegBufferClass;

G_DEFINE_TYPE(VipsForeignSaveJpegBuffer, vips_foreign_save_jpeg_buffer,
	vips_foreign_save_jpeg_get_type());

static int
vips_foreign_save_jpeg_buffer_build(VipsObject *object)
{
	VipsForeignSave *save = (VipsForeignSave *) object;
	VipsForeignSaveJpeg *jpeg = (VipsForeignSaveJpeg *) object;
	VipsForeignSaveJpegBuffer *buffer =
		(VipsForeignSaveJpegBuffer *) object;

	VipsTarget *target;
	VipsBlob *blob;

	if (VIPS_OBJECT_CLASS(vips_foreign_save_jpeg_buffer_parent_class)
			->build(object))
		return -1;

	if (!(target = vips_target_new_to_memory()))
		return -1;

	if (vips__jpeg_write_target(save->ready, target,
			jpeg->Q, save->profile, jpeg->optimize_coding,
			jpeg->interlace,
			jpeg->trellis_quant, jpeg->overshoot_deringing,
			jpeg->optimize_scans, jpeg->quant_table,
			jpeg->subsample_mode, jpeg->restart_interval)) {
		VIPS_UNREF(target);
		return -1;
	}

	g_object_get(target, "blob", &blob, NULL);
	g_object_set(buffer, "buffer", blob, NULL);
	vips_area_unref(VIPS_AREA(blob));

	VIPS_UNREF(target);

	return 0;
}

static void
vips_foreign_save_jpeg_buffer_class_init(
	VipsForeignSaveJpegBufferClass *class)
{
	GObjectClass *gobject_class = G_OBJECT_CLASS(class);
	VipsObjectClass *object_class = (VipsObjectClass *) class;

	gobject_class->set_property = vips_object_set_property;
	gobject_class->get_property = vips_object_get_property;

	object_class->nickname = "jpegsave_buffer";
	object_class->description = _("save image to jpeg buffer");
	object_class->build = vips_foreign_save_jpeg_buffer_build;

	VIPS_ARG_BOXED(class, "buffer", 1,
		_("Buffer"),
		_("Buffer to save to"),
		VIPS_ARGUMENT_REQUIRED_OUTPUT,
		G_STRUCT_OFFSET(VipsForeignSaveJpegBuffer, buf),
		VIPS_TYPE_BLOB);
}

static void
vips_foreign_save_jpeg_buffer_init(VipsForeignSaveJpegBuffer *file)
{
}

typedef struct _VipsForeignSaveJpegMime {
	VipsForeignSaveJpeg parent_object;

} VipsForeignSaveJpegMime;

typedef VipsForeignSaveJpegClass VipsForeignSaveJpegMimeClass;

G_DEFINE_TYPE(VipsForeignSaveJpegMime, vips_foreign_save_jpeg_mime,
	vips_foreign_save_jpeg_get_type());

static int
vips_foreign_save_jpeg_mime_build(VipsObject *object)
{
	VipsForeignSave *save = (VipsForeignSave *) object;
	VipsForeignSaveJpeg *jpeg = (VipsForeignSaveJpeg *) object;

	VipsTarget *target;
	VipsBlob *blob;
	const unsigned char *obuf;
	size_t olen;

	if (VIPS_OBJECT_CLASS(vips_foreign_save_jpeg_mime_parent_class)
			->build(object))
		return -1;

	if (!(target = vips_target_new_to_memory()))
		return -1;

	if (vips__jpeg_write_target(save->ready, target,
			jpeg->Q, save->profile, jpeg->optimize_coding,
			jpeg->interlace,
			jpeg->trellis_quant, jpeg->overshoot_deringing,
			jpeg->optimize_scans, jpeg->quant_table,
			jpeg->subsample_mode, jpeg->restart_interval)) {
		VIPS_UNREF(target);
		return -1;
	}

	g_object_get(target, "blob", &blob, NULL);

	obuf = vips_blob_get(blob, &olen);
	printf("Content-length: %zu\r\n", olen);
	printf("Content-type: image/jpeg\r\n");
	printf("\r\n");
	(void) fwrite(obuf, sizeof(char), olen, stdout);
	fflush(stdout);

	vips_area_unref(VIPS_AREA(blob));

	VIPS_UNREF(target);

	return 0;
}

static void
vips_foreign_save_jpeg_mime_class_init(VipsForeignSaveJpegMimeClass *class)
{
	VipsObjectClass *object_class = (VipsObjectClass *) class;

	object_class->nickname = "jpegsave_mime";
	object_class->description = _("save image to jpeg mime");
	object_class->build = vips_foreign_save_jpeg_mime_build;
}

static void
vips_foreign_save_jpeg_mime_init(VipsForeignSaveJpegMime *mime)
{
}

#endif /*HAVE_JPEG*/

/**
 * vips_jpegsave: (method)
 * @in: image to save
 * @filename: file to write to
 * @...: %NULL-terminated list of optional named arguments
 *
 * Optional arguments:
 *
 * * @Q: %gint, quality factor
 * * @optimize_coding: %gboolean, compute optimal Huffman coding tables
 * * @interlace: %gboolean, write an interlaced (progressive) jpeg
 * * @subsample_mode: #VipsForeignSubsample, chroma subsampling mode
 * * @trellis_quant: %gboolean, apply trellis quantisation to each 8x8 block
 * * @overshoot_deringing: %gboolean, overshoot samples with extreme values
 * * @optimize_scans: %gboolean, split DCT coefficients into separate scans
 * * @quant_table: %gint, quantization table index
 * * @restart_interval: %gint, restart interval in mcu
 *
 * Write a VIPS image to a file as JPEG.
 *
 * Use @Q to set the JPEG compression factor. Default 75.
 *
 * If @optimize_coding is set, the Huffman tables are optimized. This is
 * slightly slower and produces slightly smaller files.
 *
 * If @interlace is set, the jpeg files will be interlaced (progressive jpeg,
 * in jpg parlance). These files may be better for display over a slow network
 * connection, but need much more memory to encode and decode.
 *
 * Chroma subsampling is normally automatically disabled for Q >= 90. You can
 * force the subsampling mode with @subsample_mode.
 *
 * If @trellis_quant is set and the version of libjpeg supports it
 * (e.g. mozjpeg >= 3.0), apply trellis quantisation to each 8x8 block.
 * Reduces file size but increases compression time.
 *
 * If @overshoot_deringing is set and the version of libjpeg supports it
 * (e.g. mozjpeg >= 3.0), apply overshooting to samples with extreme values
 * for example 0 and 255 for 8-bit. Overshooting may reduce ringing artifacts
 * from compression, in particular in areas where black text appears on a
 * white background.
 *
 * If @optimize_scans is set and the version of libjpeg supports it
 * (e.g. mozjpeg >= 3.0), split the spectrum of DCT coefficients into
 * separate scans. Reduces file size but increases compression time.
 *
 * If @quant_table is set and the version of libjpeg supports it
 * (e.g. mozjpeg >= 3.0) it selects the quantization table to use:
 *
 * * 0 — Tables from JPEG Annex K (vips and libjpeg default)
 * * 1 — Flat table
 * * 2 — Table tuned for MSSIM on Kodak image set
 * * 3 — Table from ImageMagick by N. Robidoux (current mozjpeg default)
 * * 4 — Table tuned for PSNR-HVS-M on Kodak image set
 * * 5 — Table from Relevance of Human Vision to JPEG-DCT Compression (1992)
 * * 6 — Table from DCTune Perceptual Optimization of Compressed Dental
 *   X-Rays (1997)
 * * 7 — Table from A Visual Detection Model for DCT Coefficient
 *   Quantization (1993)
 * * 8 — Table from An Improved Detection Model for DCT Coefficient
 *   Quantization (1993)
 *
 * Quantization table 0 is the default in vips and libjpeg(-turbo), but it
 * tends to favor detail over color accuracy, producing colored patches and
 * stripes as well as heavy banding in flat areas at high compression ratios.
 * Quantization table 2 is a good candidate to try if the default quantization
 * table produces banding or color shifts and is well suited for hires images.
 * Quantization table 3 is the default in mozjpeg and has been tuned to produce
 * good results at the default quality setting; banding at high compression.
 * Quantization table 4 is the most accurate at the cost of compression ratio.
 * Tables 5-7 are based on older research papers, but generally achieve worse
 * compression ratios and/or quality than 2 or 4.
 *
 * For maximum compression with mozjpeg, a useful set of options is `strip,
 * optimize-coding, interlace, optimize-scans, trellis-quant, quant_table=3`.
 *
 * By default, the output stream won't have restart markers.  If a non-zero
 * restart_interval is specified, a restart marker will be added after each
 * specified number of MCU blocks.  This makes the stream more recoverable
 * if there are transmission errors, but also allows for some decoders to read
 * part of the JPEG without decoding the whole stream.
 *
 * The image is automatically converted to RGB, Monochrome or CMYK before
 * saving.
 *
 * EXIF data is constructed from #VIPS_META_EXIF_NAME, then
 * modified with any other related tags on the image before being written to
 * the file. #VIPS_META_RESOLUTION_UNIT is used to set the EXIF resolution
 * unit. #VIPS_META_ORIENTATION is used to set the EXIF orientation tag.
 *
 * IPTC as #VIPS_META_IPTC_NAME and XMP as #VIPS_META_XMP_NAME
 * are coded and attached.
 *
 * See also: vips_jpegsave_buffer(), vips_image_write_to_file().
 *
 * Returns: 0 on success, -1 on error.
 */
int
vips_jpegsave(VipsImage *in, const char *filename, ...)
{
	va_list ap;
	int result;

	va_start(ap, filename);
	result = vips_call_split("jpegsave", ap, in, filename);
	va_end(ap);

	return result;
}

/**
 * vips_jpegsave_target: (method)
 * @in: image to save
 * @target: save image to this target
 * @...: %NULL-terminated list of optional named arguments
 *
 * Optional arguments:
 *
 * * @Q: %gint, quality factor
 * * @optimize_coding: %gboolean, compute optimal Huffman coding tables
 * * @interlace: %gboolean, write an interlaced (progressive) jpeg
 * * @subsample_mode: #VipsForeignSubsample, chroma subsampling mode
 * * @trellis_quant: %gboolean, apply trellis quantisation to each 8x8 block
 * * @overshoot_deringing: %gboolean, overshoot samples with extreme values
 * * @optimize_scans: %gboolean, split DCT coefficients into separate scans
 * * @quant_table: %gint, quantization table index
 * * @restart_interval: %gint, restart interval in mcu
 *
 * As vips_jpegsave(), but save to a target.
 *
 * See also: vips_jpegsave(), vips_image_write_to_target().
 *
 * Returns: 0 on success, -1 on error.
 */
int
vips_jpegsave_target(VipsImage *in, VipsTarget *target, ...)
{
	va_list ap;
	int result;

	va_start(ap, target);
	result = vips_call_split("jpegsave_target", ap, in, target);
	va_end(ap);

	return result;
}

/**
 * vips_jpegsave_buffer: (method)
 * @in: image to save
 * @buf: (array length=len) (element-type guint8): return output buffer here
 * @len: (type gsize): return output length here
 * @...: %NULL-terminated list of optional named arguments
 *
 * Optional arguments:
 *
 * * @Q: %gint, quality factor
 * * @optimize_coding: %gboolean, compute optimal Huffman coding tables
 * * @interlace: %gboolean, write an interlaced (progressive) jpeg
 * * @subsample_mode: #VipsForeignSubsample, chroma subsampling mode
 * * @trellis_quant: %gboolean, apply trellis quantisation to each 8x8 block
 * * @overshoot_deringing: %gboolean, overshoot samples with extreme values
 * * @optimize_scans: %gboolean, split DCT coefficients into separate scans
 * * @quant_table: %gint, quantization table index
 * * @restart_interval: %gint, restart interval in mcu
 *
 * As vips_jpegsave(), but save to a memory buffer.
 *
 * The address of the buffer is returned in @obuf, the length of the buffer in
 * @olen. You are responsible for freeing the buffer with g_free() when you
 * are done with it.
 *
 * See also: vips_jpegsave(), vips_image_write_to_file().
 *
 * Returns: 0 on success, -1 on error.
 */
int
vips_jpegsave_buffer(VipsImage *in, void **buf, size_t *len, ...)
{
	va_list ap;
	VipsArea *area;
	int result;

	area = NULL;

	va_start(ap, len);
	result = vips_call_split("jpegsave_buffer", ap, in, &area);
	va_end(ap);

	if (!result &&
		area) {
		if (buf) {
			*buf = area->data;
			area->free_fn = NULL;
		}
		if (len)
			*len = area->length;

		vips_area_unref(area);
	}

	return result;
}

/**
 * vips_jpegsave_mime: (method)
 * @in: image to save
 * @...: %NULL-terminated list of optional named arguments
 *
 * Optional arguments:
 *
 * * @Q: %gint, quality factor
 * * @optimize_coding: %gboolean, compute optimal Huffman coding tables
 * * @interlace: %gboolean, write an interlaced (progressive) jpeg
 * * @subsample_mode: #VipsForeignSubsample, chroma subsampling mode
 * * @trellis_quant: %gboolean, apply trellis quantisation to each 8x8 block
 * * @overshoot_deringing: %gboolean, overshoot samples with extreme values
 * * @optimize_scans: %gboolean, split DCT coefficients into separate scans
 * * @quant_table: %gint, quantization table index
 * * @restart_interval: %gint, restart interval in mcu
 *
 * As vips_jpegsave(), but save as a mime jpeg on stdout.
 *
 * See also: vips_jpegsave(), vips_image_write_to_file().
 *
 * Returns: 0 on success, -1 on error.
 */
int
vips_jpegsave_mime(VipsImage *in, ...)
{
	va_list ap;
	int result;

	va_start(ap, in);
	result = vips_call_split("jpegsave_mime", ap, in);
	va_end(ap);

	return result;
}
