[vlc-commits] codec: jpeg encoder implemented
Maxim Bublis
git at videolan.org
Tue Feb 4 13:50:33 CET 2014
vlc | branch: master | Maxim Bublis <b at codemonkey.ru> | Mon Feb 3 13:50:43 2014 +0400| [e868212d51f4fdf5fa1dda7f44737586032ba848] | committer: Rafaël Carré
codec: jpeg encoder implemented
This patch implements jpeg encoder using libjpeg.
Signed-off-by: Rafaël Carré <funman at videolan.org>
> http://git.videolan.org/gitweb.cgi/vlc.git/?a=commit;h=e868212d51f4fdf5fa1dda7f44737586032ba848
---
modules/codec/jpeg.c | 182 ++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 182 insertions(+)
diff --git a/modules/codec/jpeg.c b/modules/codec/jpeg.c
index fb67f66..7004fcd 100644
--- a/modules/codec/jpeg.c
+++ b/modules/codec/jpeg.c
@@ -45,6 +45,12 @@
\
/**@}*/ \
+#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 common descriptor
*/
@@ -71,15 +77,49 @@ 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
+
+ struct jpeg_compress_struct p_jpeg;
+
+ int i_blocksize;
+ 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, true)
vlc_module_end()
@@ -246,3 +286,145 @@ 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 */
+ encoder_sys_t *p_sys = malloc(sizeof(encoder_sys_t));
+ if (p_sys == NULL)
+ {
+ return VLC_ENOMEM;
+ }
+
+ p_enc->p_sys = p_sys;
+
+ p_sys->p_obj = p_this;
+
+ p_sys->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;
+
+ p_sys->i_quality = var_GetInteger(p_enc, ENC_CFG_PREFIX "quality");
+ p_sys->i_blocksize = 3 * p_enc->fmt_in.video.i_visible_width * p_enc->fmt_in.video.i_visible_height;
+
+ p_enc->fmt_in.i_codec = VLC_CODEC_J420;
+ p_enc->pf_encode_video = EncodeBlock;
+
+ return VLC_SUCCESS;
+}
+
+/*
+ * EncodeBlock
+ */
+static block_t *EncodeBlock(encoder_t *p_enc, picture_t *p_pic)
+{
+ encoder_sys_t *p_sys = p_enc->p_sys;
+
+ block_t *p_block = block_Alloc(p_sys->i_blocksize);
+ if (p_block == NULL)
+ {
+ return NULL;
+ }
+
+ JSAMPIMAGE p_row_pointers = NULL;
+
+ /* libjpeg longjmp's there in case of error */
+ if (setjmp(p_sys->setjmp_buffer))
+ {
+ goto error;
+ }
+
+ jpeg_create_compress(&p_sys->p_jpeg);
+ jpeg_mem_dest(&p_sys->p_jpeg, &p_block->p_buffer, &p_block->i_buffer);
+
+ p_sys->p_jpeg.image_width = p_enc->fmt_in.video.i_visible_width;
+ p_sys->p_jpeg.image_height = p_enc->fmt_in.video.i_visible_height;
+ p_sys->p_jpeg.input_components = 3;
+ p_sys->p_jpeg.in_color_space = JCS_YCbCr;
+
+ jpeg_set_defaults(&p_sys->p_jpeg);
+ jpeg_set_colorspace(&p_sys->p_jpeg, JCS_YCbCr);
+
+ p_sys->p_jpeg.raw_data_in = TRUE;
+ p_sys->p_jpeg.do_fancy_downsampling = FALSE;
+
+ jpeg_set_quality(&p_sys->p_jpeg, p_sys->i_quality, TRUE);
+
+ jpeg_start_compress(&p_sys->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_sys->p_jpeg.comp_info[i].v_samp_factor * DCTSIZE);
+ }
+
+ while (p_sys->p_jpeg.next_scanline < p_sys->p_jpeg.image_height)
+ {
+ for (int i = 0; i < p_pic->i_planes; i++)
+ {
+ int i_offset = p_sys->p_jpeg.next_scanline * p_sys->p_jpeg.comp_info[i].v_samp_factor / p_sys->p_jpeg.max_v_samp_factor;
+
+ for (int j = 0; j < p_sys->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 * (i_offset + j);
+ }
+ }
+ jpeg_write_raw_data(&p_sys->p_jpeg, p_row_pointers, p_sys->p_jpeg.max_v_samp_factor * DCTSIZE);
+ }
+
+ jpeg_finish_compress(&p_sys->p_jpeg);
+ jpeg_destroy_compress(&p_sys->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_sys->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);
+}
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