[vlc-devel] [PATCH v3] codec: jpeg encoder implemented
Maxim Bublis
b at codemonkey.ru
Wed Jan 29 14:43:38 CET 2014
This patch implements jpeg encoder using libjpeg.
---
modules/codec/jpeg.c | 256 +++++++++++++++++++++++++++++++++++++++++++++------
1 file changed, 226 insertions(+), 30 deletions(-)
diff --git a/modules/codec/jpeg.c b/modules/codec/jpeg.c
index ad09d56..51ba21f 100644
--- a/modules/codec/jpeg.c
+++ b/modules/codec/jpeg.c
@@ -1,7 +1,7 @@
/*****************************************************************************
* jpeg.c: jpeg decoder module making use of libjpeg.
*****************************************************************************
- * Copyright (C) 2013 VLC authors and VideoLAN
+ * Copyright (C) 2013-2014 VLC authors and VideoLAN
*
* Authors: Maxim Bublis <b at codemonkey.ru>
*
@@ -30,18 +30,43 @@
#include <jpeglib.h>
#include <setjmp.h>
+/* JPEG_SYS_COMMON_MEMBERS:
+ * members common to encoder and decoder descriptors
+ */
+#define JPEG_SYS_COMMON_MEMBERS \
+/**@{*/ \
+ /* libjpeg error handler manager */ \
+ struct jpeg_error_mgr err; \
+ \
+ /* setjmp buffer for internal libjpeg error handling */ \
+ jmp_buf setjmp_buffer; \
+ \
+ vlc_object_t *p_obj; \
+ \
+/**@}*/ \
+
+#define ENC_CFG_PREFIX "sout-jpeg-"
+#define ENC_QUALITY_TEXT N_("Quality level")
+#define ENC_QUALITY_LONGTEXT N_("Quality level " \
+ "for encoding (this can enlarge or reduce output image size).")
+
+
/*
- * jpeg decoder descriptor
+ * jpeg common descriptor
*/
-struct decoder_sys_t
+struct jpeg_sys_t
{
- /* libjpeg error handler manager */
- struct jpeg_error_mgr err;
+ JPEG_SYS_COMMON_MEMBERS
+};
- /* setjmp buffer for internal libjpeg error handling */
- jmp_buf setjmp_buffer;
+typedef struct jpeg_sys_t jpeg_sys_t;
- decoder_t *p_dec;
+/*
+ * jpeg decoder descriptor
+ */
+struct decoder_sys_t
+{
+ JPEG_SYS_COMMON_MEMBERS
};
static int OpenDecoder(vlc_object_t *);
@@ -50,17 +75,71 @@ static void CloseDecoder(vlc_object_t *);
static picture_t *DecodeBlock(decoder_t *, block_t **);
/*
+ * jpeg encoder descriptor
+ */
+struct encoder_sys_t
+{
+ JPEG_SYS_COMMON_MEMBERS
+
+ int i_quality;
+};
+
+static const char * const ppsz_enc_options[] = {
+ "quality",
+ NULL
+};
+
+static int OpenEncoder(vlc_object_t *);
+static void CloseEncoder(vlc_object_t *);
+
+static block_t *EncodeBlock(encoder_t *, picture_t *);
+
+/*
* Module descriptor
*/
vlc_module_begin()
set_category(CAT_INPUT)
set_subcategory(SUBCAT_INPUT_VCODEC)
+ /* decoder main module */
set_description(N_("JPEG image decoder"))
set_capability("decoder", 1000)
set_callbacks(OpenDecoder, CloseDecoder)
add_shortcut("jpeg")
+
+ /* encoder submodule */
+ add_submodule()
+ add_shortcut("jpeg")
+ set_section(N_("Encoding"), NULL)
+ set_description(N_("JPEG image encoder"))
+ set_capability("encoder", 1000)
+ set_callbacks(OpenEncoder, CloseEncoder)
+ add_integer_with_range(ENC_CFG_PREFIX "quality", 95, 0, 100,
+ ENC_QUALITY_TEXT, ENC_QUALITY_LONGTEXT, false)
vlc_module_end()
+
+/*
+ * Exit error handler for libjpeg
+ */
+static void user_error_exit(j_common_ptr p_jpeg)
+{
+ jpeg_sys_t *p_sys = (jpeg_sys_t *)p_jpeg->err;
+ p_sys->err.output_message(p_jpeg);
+ longjmp(p_sys->setjmp_buffer, 1);
+}
+
+/*
+ * Emit message error handler for libjpeg
+ */
+static void user_error_message(j_common_ptr p_jpeg)
+{
+ char error_msg[JMSG_LENGTH_MAX];
+
+ jpeg_sys_t *p_sys = (jpeg_sys_t *)p_jpeg->err;
+ p_sys->err.format_message(p_jpeg, error_msg);
+ msg_Err(p_sys->p_obj, "%s", error_msg);
+}
+
/*
* Probe the decoder and return score
*/
@@ -80,7 +159,7 @@ static int OpenDecoder(vlc_object_t *p_this)
return VLC_ENOMEM;
}
- p_dec->p_sys->p_dec = p_dec;
+ p_dec->p_sys->p_obj = p_this;
/* Set output properties */
p_dec->fmt_out.i_cat = VIDEO_ES;
@@ -91,27 +170,6 @@ static int OpenDecoder(vlc_object_t *p_this)
return VLC_SUCCESS;
}
-/*
- * Exit error handler for libjpeg
- */
-static void user_error_exit(j_common_ptr p_jpeg)
-{
- decoder_sys_t *p_sys = (decoder_sys_t *)p_jpeg->err;
- p_sys->err.output_message(p_jpeg);
- longjmp(p_sys->setjmp_buffer, 1);
-}
-
-/*
- * Emit message error handler for libjpeg
- */
-static void user_error_message(j_common_ptr p_jpeg)
-{
- char error_msg[JMSG_LENGTH_MAX];
-
- decoder_sys_t *p_sys = (decoder_sys_t *)p_jpeg->err;
- p_sys->err.format_message(p_jpeg, error_msg);
- msg_Err(p_sys->p_dec, "%s", error_msg);
-}
/*
* This function must be fed with a complete compressed frame.
@@ -222,3 +280,141 @@ static void CloseDecoder(vlc_object_t *p_this)
free(p_sys);
}
+
+/*
+ * Probe the encoder and return score
+ */
+static int OpenEncoder(vlc_object_t *p_this)
+{
+ encoder_t *p_enc = (encoder_t *)p_this;
+
+ config_ChainParse(p_enc, ENC_CFG_PREFIX, ppsz_enc_options, p_enc->p_cfg);
+
+ if (p_enc->fmt_out.i_codec != VLC_CODEC_JPEG)
+ {
+ return VLC_EGENERIC;
+ }
+
+ /* Allocate the memory needed to store encoder's structure */
+ p_enc->p_sys = malloc(sizeof(encoder_sys_t));
+ if (p_enc->p_sys == NULL)
+ {
+ return VLC_ENOMEM;
+ }
+
+ p_enc->p_sys->p_obj = p_this;
+
+ p_enc->pf_encode_video = EncodeBlock;
+
+ p_enc->p_sys->i_quality = var_GetInteger(p_enc, ENC_CFG_PREFIX "quality");
+
+ return VLC_SUCCESS;
+}
+
+static block_t *EncodeBlock(encoder_t *p_enc, picture_t *p_pic)
+{
+ encoder_sys_t *p_sys = p_enc->p_sys;
+
+ const int bytesPerPixel = p_enc->fmt_out.video.i_bits_per_pixel ?
+ p_enc->fmt_out.video.i_bits_per_pixel / 8 : 3;
+ const int blocksize = bytesPerPixel * p_enc->fmt_in.video.i_visible_width * p_enc->fmt_in.video.i_visible_height;
+
+ block_t *p_block = block_Alloc(blocksize);
+ if (p_block == NULL)
+ {
+ return NULL;
+ }
+
+ struct jpeg_compress_struct p_jpeg;
+ JSAMPIMAGE p_row_pointers = NULL;
+
+ p_jpeg.err = jpeg_std_error(&p_sys->err);
+ p_sys->err.error_exit = user_error_exit;
+ p_sys->err.output_message = user_error_message;
+
+ /* libjpeg longjmp's there in case of error */
+ if (setjmp(p_sys->setjmp_buffer))
+ {
+ goto error;
+ }
+
+ jpeg_create_compress(&p_jpeg);
+ jpeg_mem_dest(&p_jpeg, &p_block->p_buffer, &p_block->i_buffer);
+
+ p_jpeg.image_width = p_enc->fmt_in.video.i_visible_width;
+ p_jpeg.image_height = p_enc->fmt_in.video.i_visible_height;
+ p_jpeg.input_components = bytesPerPixel;
+ p_jpeg.in_color_space = JCS_YCbCr;
+
+ jpeg_set_defaults(&p_jpeg);
+ jpeg_set_colorspace(&p_jpeg, JCS_YCbCr);
+
+ p_jpeg.raw_data_in = TRUE;
+ p_jpeg.do_fancy_downsampling = FALSE;
+
+ jpeg_set_quality(&p_jpeg, p_sys->i_quality, TRUE);
+
+ jpeg_start_compress(&p_jpeg, TRUE);
+
+ /* Encode picture */
+ p_row_pointers = malloc(sizeof(JSAMPARRAY) * p_pic->i_planes);
+ if (p_row_pointers == NULL)
+ {
+ goto error;
+ }
+
+ for (int i = 0; i < p_pic->i_planes; i++)
+ {
+ p_row_pointers[i] = malloc(sizeof(JSAMPROW) * p_jpeg.comp_info[i].v_samp_factor * DCTSIZE);
+ }
+
+ while (p_jpeg.next_scanline < p_jpeg.image_height)
+ {
+ for (int i = 0; i < p_pic->i_planes; i++)
+ {
+ for (int j = 0; j < p_jpeg.comp_info[i].v_samp_factor * DCTSIZE; j++)
+ {
+ p_row_pointers[i][j] = p_pic->p[i].p_pixels + p_pic->p[i].i_pitch * p_jpeg.next_scanline * p_jpeg.comp_info[i].v_samp_factor / p_jpeg.max_v_samp_factor + j;
+ }
+ }
+ jpeg_write_raw_data(&p_jpeg, p_row_pointers, p_jpeg.max_v_samp_factor * DCTSIZE);
+ }
+
+ jpeg_finish_compress(&p_jpeg);
+ jpeg_destroy_compress(&p_jpeg);
+
+ for (int i = 0; i < p_pic->i_planes; i++)
+ {
+ free(p_row_pointers[i]);
+ }
+ free(p_row_pointers);
+
+ return p_block;
+
+error:
+ jpeg_destroy_compress(&p_jpeg);
+
+ if (p_row_pointers != NULL)
+ {
+ for (int i = 0; i < p_pic->i_planes; i++)
+ {
+ free(p_row_pointers[i]);
+ }
+ }
+ free(p_row_pointers);
+
+ block_Release(p_block);
+
+ return NULL;
+}
+
+/*
+ * jpeg encoder destruction
+ */
+static void CloseEncoder(vlc_object_t *p_this)
+{
+ encoder_t *p_enc = (encoder_t *)p_this;
+ encoder_sys_t *p_sys = p_enc->p_sys;
+
+ free(p_sys);
+}
--
1.8.3.4 (Apple Git-47)
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