/* GStreamer

 * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Library General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library 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

 * Library General Public License for more details.

 *

 * You should have received a copy of the GNU Library General Public

 * License along with this library; if not, write to the

 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,

 * Boston, MA 02111-1307, USA.

 */

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include <string.h>

#include "gstjpegdec.h"

#include <gst/video/video.h>

#include "gst/gst-i18n-plugin.h"

#include <jerror.h>

static const GstElementDetails gst_jpeg_dec_details =

GST_ELEMENT_DETAILS ("JPEG image decoder",

    "Codec/Decoder/Image",

    "Decode images from JPEG format",

    "Wim Taymans <wim.taymans@tvd.be>");

#define MIN_WIDTH  16

#define MAX_WIDTH  4096

#define MIN_HEIGHT 16

#define MAX_HEIGHT 4096

static GstStaticPadTemplate gst_jpeg_dec_src_pad_template =

GST_STATIC_PAD_TEMPLATE ("src",

    GST_PAD_SRC,

    GST_PAD_ALWAYS,

    GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("I420"))

    );

static GstStaticPadTemplate gst_jpeg_dec_sink_pad_template =

GST_STATIC_PAD_TEMPLATE ("sink",

    GST_PAD_SINK,

    GST_PAD_ALWAYS,

    GST_STATIC_CAPS ("image/jpeg, "

        "width = (int) [ " G_STRINGIFY (MIN_WIDTH) ", " G_STRINGIFY (MAX_WIDTH)

        " ], " "height = (int) [ " G_STRINGIFY (MIN_HEIGHT) ", "

        G_STRINGIFY (MAX_HEIGHT) " ], " "framerate = (fraction) [ 0/1, MAX ]")

    );

GST_DEBUG_CATEGORY_STATIC (jpeg_dec_debug);

#define GST_CAT_DEFAULT jpeg_dec_debug

/* These macros are adapted from videotestsrc.c 

 *  and/or gst-plugins/gst/games/gstvideoimage.c */

#define I420_Y_ROWSTRIDE(width) (GST_ROUND_UP_4(width))

#define I420_U_ROWSTRIDE(width) (GST_ROUND_UP_8(width)/2)

#define I420_V_ROWSTRIDE(width) ((GST_ROUND_UP_8(I420_Y_ROWSTRIDE(width)))/2)

#define I420_Y_OFFSET(w,h) (0)

#define I420_U_OFFSET(w,h) (I420_Y_OFFSET(w,h)+(I420_Y_ROWSTRIDE(w)*GST_ROUND_UP_2(h)))

#define I420_V_OFFSET(w,h) (I420_U_OFFSET(w,h)+(I420_U_ROWSTRIDE(w)*GST_ROUND_UP_2(h)/2))

#define I420_SIZE(w,h)     (I420_V_OFFSET(w,h)+(I420_V_ROWSTRIDE(w)*GST_ROUND_UP_2(h)/2))

static GstElementClass *parent_class;   /* NULL */

static void gst_jpeg_dec_base_init (gpointer g_class);

static void gst_jpeg_dec_class_init (GstJpegDecClass * klass);

static void gst_jpeg_dec_init (GstJpegDec * jpegdec);

static GstFlowReturn gst_jpeg_dec_chain (GstPad * pad, GstBuffer * buffer);

static gboolean gst_jpeg_dec_setcaps (GstPad * pad, GstCaps * caps);

static GstStateChangeReturn gst_jpeg_dec_change_state (GstElement * element,

    GstStateChange transition);

GType

gst_jpeg_dec_get_type (void)

{

  static GType type = 0;

  if (!type) {

    static const GTypeInfo jpeg_dec_info = {

      sizeof (GstJpegDecClass),

      (GBaseInitFunc) gst_jpeg_dec_base_init,

      NULL,

      (GClassInitFunc) gst_jpeg_dec_class_init,

      NULL,

      NULL,

      sizeof (GstJpegDec),

      0,

      (GInstanceInitFunc) gst_jpeg_dec_init,

    };

    type = g_type_register_static (GST_TYPE_ELEMENT, "GstJpegDec",

        &jpeg_dec_info, 0);

  }

  return type;

}

static void

gst_jpeg_dec_finalize (GObject * object)

{

  GstJpegDec *dec = GST_JPEG_DEC (object);

  jpeg_destroy_decompress (&dec->cinfo);

  if (dec->tempbuf)

    gst_buffer_unref (dec->tempbuf);

  G_OBJECT_CLASS (parent_class)->finalize (object);

}

static void

gst_jpeg_dec_base_init (gpointer g_class)

{

  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);

  gst_element_class_add_pad_template (element_class,

      gst_static_pad_template_get (&gst_jpeg_dec_src_pad_template));

  gst_element_class_add_pad_template (element_class,

      gst_static_pad_template_get (&gst_jpeg_dec_sink_pad_template));

  gst_element_class_set_details (element_class, &gst_jpeg_dec_details);

}

static void

gst_jpeg_dec_class_init (GstJpegDecClass * klass)

{

  GstElementClass *gstelement_class;

  GObjectClass *gobject_class;

  gstelement_class = (GstElementClass *) klass;

  gobject_class = (GObjectClass *) klass;

  parent_class = g_type_class_peek_parent (klass);

  gobject_class->finalize = gst_jpeg_dec_finalize;

  gstelement_class->change_state =

      GST_DEBUG_FUNCPTR (gst_jpeg_dec_change_state);

  GST_DEBUG_CATEGORY_INIT (jpeg_dec_debug, "jpegdec", 0, "JPEG decoder");

}

static gboolean

gst_jpeg_dec_fill_input_buffer (j_decompress_ptr cinfo)

{

/*

  struct GstJpegDecSourceMgr *src_mgr;

  GstJpegDec *dec;

  src_mgr = (struct GstJpegDecSourceMgr*) &cinfo->src;

  dec = GST_JPEG_DEC (src_mgr->dec);

*/

  GST_DEBUG ("fill_input_buffer");

/*

  g_return_val_if_fail (dec != NULL, TRUE);

  src_mgr->pub.next_input_byte = GST_BUFFER_DATA (dec->tempbuf);

  src_mgr->pub.bytes_in_buffer = GST_BUFFER_SIZE (dec->tempbuf);

*/

  return TRUE;

}

static void

gst_jpeg_dec_init_source (j_decompress_ptr cinfo)

{

  GST_DEBUG ("init_source");

}

static void

gst_jpeg_dec_skip_input_data (j_decompress_ptr cinfo, glong num_bytes)

{

  GST_DEBUG ("skip_input_data: %ld bytes", num_bytes);

  if (num_bytes > 0 && cinfo->src->bytes_in_buffer >= num_bytes) {

    cinfo->src->next_input_byte += (size_t) num_bytes;

    cinfo->src->bytes_in_buffer -= (size_t) num_bytes;

  }

}

static gboolean

gst_jpeg_dec_resync_to_restart (j_decompress_ptr cinfo, gint desired)

{

  GST_DEBUG ("resync_to_start");

  return TRUE;

}

static void

gst_jpeg_dec_term_source (j_decompress_ptr cinfo)

{

  GST_DEBUG ("term_source");

  return;

}

METHODDEF (void)

    gst_jpeg_dec_my_output_message (j_common_ptr cinfo)

{

  return;                       /* do nothing */

}

METHODDEF (void)

    gst_jpeg_dec_my_emit_message (j_common_ptr cinfo, int msg_level)

{

  /* GST_DEBUG ("emit_message: msg_level = %d", msg_level); */

  return;

}

METHODDEF (void)

    gst_jpeg_dec_my_error_exit (j_common_ptr cinfo)

{

  struct GstJpegDecErrorMgr *err_mgr = (struct GstJpegDecErrorMgr *) cinfo->err;

  (*cinfo->err->output_message) (cinfo);

  longjmp (err_mgr->setjmp_buffer, 1);

}

static void

gst_jpeg_dec_init (GstJpegDec * dec)

{

  GST_DEBUG ("initializing");

  /* create the sink and src pads */

  dec->sinkpad =

      gst_pad_new_from_static_template (&gst_jpeg_dec_sink_pad_template,

      "sink");

  gst_element_add_pad (GST_ELEMENT (dec), dec->sinkpad);

  gst_pad_set_setcaps_function (dec->sinkpad,

      GST_DEBUG_FUNCPTR (gst_jpeg_dec_setcaps));

  gst_pad_set_chain_function (dec->sinkpad,

      GST_DEBUG_FUNCPTR (gst_jpeg_dec_chain));

  dec->srcpad =

      gst_pad_new_from_static_template (&gst_jpeg_dec_src_pad_template, "src");

  gst_element_add_pad (GST_ELEMENT (dec), dec->srcpad);

  /* setup jpeglib */

  memset (&dec->cinfo, 0, sizeof (dec->cinfo));

  memset (&dec->jerr, 0, sizeof (dec->jerr));

  dec->cinfo.err = jpeg_std_error (&dec->jerr.pub);

  dec->jerr.pub.output_message = gst_jpeg_dec_my_output_message;

  dec->jerr.pub.emit_message = gst_jpeg_dec_my_emit_message;

  dec->jerr.pub.error_exit = gst_jpeg_dec_my_error_exit;

  jpeg_create_decompress (&dec->cinfo);

  dec->cinfo.src = (struct jpeg_source_mgr *) &dec->jsrc;

  dec->cinfo.src->init_source = gst_jpeg_dec_init_source;

  dec->cinfo.src->fill_input_buffer = gst_jpeg_dec_fill_input_buffer;

  dec->cinfo.src->skip_input_data = gst_jpeg_dec_skip_input_data;

  dec->cinfo.src->resync_to_restart = gst_jpeg_dec_resync_to_restart;

  dec->cinfo.src->term_source = gst_jpeg_dec_term_source;

  dec->jsrc.dec = dec;

}

static inline gboolean

is_jpeg_start_marker (const guint8 * data)

{

  return (data[0] == 0xff && data[1] == 0xd8);

}

static inline gboolean

is_jpeg_end_marker (const guint8 * data)

{

  return (data[0] == 0xff && data[1] == 0xd9);

}

static gboolean

gst_jpeg_dec_find_jpeg_header (GstJpegDec * dec)

{

  const guint8 *data;

  guint size;

  data = GST_BUFFER_DATA (dec->tempbuf);

  size = GST_BUFFER_SIZE (dec->tempbuf);

  g_return_val_if_fail (size >= 2, FALSE);

  while (!is_jpeg_start_marker (data) || data[2] != 0xff) {

    const guint8 *marker;

    GstBuffer *tmp;

    guint off;

    marker = memchr (data + 1, 0xff, size - 1 - 2);

    if (marker == NULL) {

      off = size - 1;           /* keep last byte */

    } else {

      off = marker - data;

    }

    tmp = gst_buffer_create_sub (dec->tempbuf, off, size - off);

    gst_buffer_unref (dec->tempbuf);

    dec->tempbuf = tmp;

    data = GST_BUFFER_DATA (dec->tempbuf);

    size = GST_BUFFER_SIZE (dec->tempbuf);

    if (size < 2)

      return FALSE;             /* wait for more data */

  }

  return TRUE;                  /* got header */

}

static gboolean

gst_jpeg_dec_ensure_header (GstJpegDec * dec)

{

  g_return_val_if_fail (dec->tempbuf != NULL, FALSE);

check_header:

  /* we need at least a start marker (0xff 0xd8)

   *   and an end marker (0xff 0xd9) */

  if (GST_BUFFER_SIZE (dec->tempbuf) <= 4) {

    GST_DEBUG ("Not enough data");

    return FALSE;               /* we need more data */

  }

  if (!is_jpeg_start_marker (GST_BUFFER_DATA (dec->tempbuf))) {

    GST_DEBUG ("Not a JPEG header, resyncing to header...");

    if (!gst_jpeg_dec_find_jpeg_header (dec)) {

      GST_DEBUG ("No JPEG header in current buffer");

      return FALSE;             /* we need more data */

    }

    GST_DEBUG ("Found JPEG header");

    goto check_header;          /* buffer might have changed */

  }

  return TRUE;

}

#if 0

static gboolean

gst_jpeg_dec_have_end_marker (GstJpegDec * dec)

{

  guint8 *data = GST_BUFFER_DATA (dec->tempbuf);

  guint size = GST_BUFFER_SIZE (dec->tempbuf);

  return (size > 2 && data && is_jpeg_end_marker (data + size - 2));

}

#endif

static inline gboolean

gst_jpeg_dec_parse_tag_has_entropy_segment (guint8 tag)

{

  if (tag == 0xda || (tag >= 0xd0 && tag <= 0xd7))

    return TRUE;

  return FALSE;

}

/* returns image length in bytes if parsed 

 * successfully, otherwise 0 */

static guint

gst_jpeg_dec_parse_image_data (GstJpegDec * dec)

{

  guint8 *start, *data, *end;

  guint size;

  size = GST_BUFFER_SIZE (dec->tempbuf);

  start = GST_BUFFER_DATA (dec->tempbuf);

  end = start + size;

  data = start;

  g_return_val_if_fail (is_jpeg_start_marker (data), 0);

  GST_DEBUG ("Parsing jpeg image data (%u bytes)", size);

  /* skip start marker */

  data += 2;

  while (1) {

    guint frame_len;

    /* enough bytes left for EOI marker? (we need 0xff 0xNN, thus end-1) */

    if (data >= end - 1) {

      GST_DEBUG ("at end of input and no EOI marker found, need more data");

      return 0;

    }

    if (is_jpeg_end_marker (data)) {

      GST_DEBUG ("0x%08x: end marker", data - start);

      goto found_eoi;

    }

    /* do we need to resync? */

    if (*data != 0xff) {

      GST_DEBUG ("Lost sync at 0x%08x, resyncing", data - start);

      /* at the very least we expect 0xff 0xNN, thus end-1 */

      while (*data != 0xff && data < end - 1)

        ++data;

      if (is_jpeg_end_marker (data)) {

        GST_DEBUG ("resynced to end marker");

        goto found_eoi;

      }

      /* we need 0xFF 0xNN 0xLL 0xLL */

      if (data >= end - 1 - 2) {

        GST_DEBUG ("at end of input, without new sync, need more data");

        return 0;

      }

      /* check if we will still be in sync if we interpret

       * this as a sync point and skip this frame */

      frame_len = GST_READ_UINT16_BE (data + 2);

      GST_DEBUG ("possible sync at 0x%08x, frame_len=%u", data - start,

          frame_len);

      if (data + 2 + frame_len >= end - 1 || data[2 + frame_len] != 0xff) {

        /* ignore and continue resyncing until we hit the end

         * of our data or find a sync point that looks okay */

        ++data;

        continue;

      }

      GST_DEBUG ("found sync at 0x%08x", data - size);

    }

    while (*data == 0xff)

      ++data;

    if (data + 2 >= end)

      return 0;

    if (*data >= 0xd0 && *data <= 0xd7)

      frame_len = 0;

    else

      frame_len = GST_READ_UINT16_BE (data + 1);

    GST_DEBUG ("0x%08x: tag %02x, frame_len=%u", data - start - 1, *data,

        frame_len);

    /* the frame length includes the 2 bytes for the length; here we want at

     * least 2 more bytes at the end for an end marker, thus end-2 */

    if (data + 1 + frame_len >= end - 2) {

      /* theoretically we could have lost sync and not really need more

       * data, but that's just tough luck and a broken image then */

      GST_DEBUG ("at end of input and no EOI marker found, need more data");

      return 0;

    }

    if (gst_jpeg_dec_parse_tag_has_entropy_segment (*data)) {

      guint8 *d2 = data + 1 + frame_len;

      guint eseglen = 0;

      GST_DEBUG ("0x%08x: finding entropy segment length", data - start - 1);

      while (1) {

        if (d2[eseglen] == 0xff && d2[eseglen + 1] != 0x00)

          break;

        if (d2 + eseglen >= end - 1)

          return 0;             /* need more data */

        ++eseglen;

      }

      frame_len += eseglen;

      GST_DEBUG ("entropy segment length=%u => frame_len=%u", eseglen,

          frame_len);

    }

    data += 1 + frame_len;

  }

found_eoi:

  /* data is assumed to point to the 0xff sync point of the

   *  EOI marker (so there is one more byte after that) */

  g_assert (is_jpeg_end_marker (data));

  return ((data + 1) - start + 1);

}

/* shamelessly ripped from jpegutils.c in mjpegtools */

static void

add_huff_table (j_decompress_ptr dinfo,

    JHUFF_TBL ** htblptr, const UINT8 * bits, const UINT8 * val)

/* Define a Huffman table */

{

  int nsymbols, len;

  if (*htblptr == NULL)

    *htblptr = jpeg_alloc_huff_table ((j_common_ptr) dinfo);

  /* Copy the number-of-symbols-of-each-code-length counts */

  memcpy ((*htblptr)->bits, bits, sizeof ((*htblptr)->bits));

  /* Validate the counts.  We do this here mainly so we can copy the right

   * number of symbols from the val[] array, without risking marching off

   * the end of memory.  jchuff.c will do a more thorough test later.

   */

  nsymbols = 0;

  for (len = 1; len <= 16; len++)

    nsymbols += bits[len];

  if (nsymbols < 1 || nsymbols > 256)

    g_error ("jpegutils.c:  add_huff_table failed badly. ");

  memcpy ((*htblptr)->huffval, val, nsymbols * sizeof (UINT8));

}

static void

std_huff_tables (j_decompress_ptr dinfo)

/* Set up the standard Huffman tables (cf. JPEG standard section K.3) */

/* IMPORTANT: these are only valid for 8-bit data precision! */

{

  static const UINT8 bits_dc_luminance[17] =

      { /* 0-base */ 0, 0, 1, 5, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0 };

  static const UINT8 val_dc_luminance[] =

      { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };

  static const UINT8 bits_dc_chrominance[17] =

      { /* 0-base */ 0, 0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0 };

  static const UINT8 val_dc_chrominance[] =

      { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };

  static const UINT8 bits_ac_luminance[17] =

      { /* 0-base */ 0, 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 0x7d };

  static const UINT8 val_ac_luminance[] =

      { 0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12,

    0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07,

    0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08,

    0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52, 0xd1, 0xf0,

    0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16,

    0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28,

    0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,

    0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49,

    0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,

    0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,

    0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79,

    0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,

    0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,

    0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,

    0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6,

    0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5,

    0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4,