On Thu, 23. Apr 00:04, gautamr...@gmail.com wrote:
> From: Gautam Ramakrishnan <gautamr...@gmail.com>
>
> This patch adds support for decoding images
> with a Region of Interest. Allows decoding
> samples such as p0_03.j2k. This patch should
> fix ticket #4681.
> ---
> libavcodec/jpeg2000.h | 1 +
> libavcodec/jpeg2000dec.c | 67 ++++++++++++++++++++++++++++++++++++++--
> 2 files changed, 65 insertions(+), 3 deletions(-)
>
> diff --git a/libavcodec/jpeg2000.h b/libavcodec/jpeg2000.h
> index 7b78c0193e..0f82716981 100644
> --- a/libavcodec/jpeg2000.h
> +++ b/libavcodec/jpeg2000.h
> @@ -210,6 +210,7 @@ typedef struct Jpeg2000Component {
> int *i_data;
> int coord[2][2]; // border coordinates {{x0, x1}, {y0, y1}} -- can be
> reduced with lowres option
> int coord_o[2][2]; // border coordinates {{x0, x1}, {y0, y1}} --
> original values from jpeg2000 headers
> + uint8_t roi_shift; // ROI scaling value for the component
> } Jpeg2000Component;
>
> /* misc tools */
> diff --git a/libavcodec/jpeg2000dec.c b/libavcodec/jpeg2000dec.c
> index 5a7d9e7882..bcc6cc628b 100644
> --- a/libavcodec/jpeg2000dec.c
> +++ b/libavcodec/jpeg2000dec.c
> @@ -117,6 +117,7 @@ typedef struct Jpeg2000DecoderContext {
> Jpeg2000CodingStyle codsty[4];
> Jpeg2000QuantStyle qntsty[4];
> Jpeg2000POC poc;
> + uint8_t roi_shift[4];
>
> int bit_index;
>
> @@ -598,6 +599,31 @@ static int get_coc(Jpeg2000DecoderContext *s,
> Jpeg2000CodingStyle *c,
> return 0;
> }
>
> +static int get_rgn(Jpeg2000DecoderContext *s, int n)
> +{
> + uint16_t compno;
> + compno = (s->ncomponents < 257)? bytestream2_get_byte(&s->g):
> + bytestream2_get_be16u(&s->g);
> + if (bytestream2_get_byte(&s->g)) {
> + av_log(s->avctx, AV_LOG_ERROR, "Invalid RGN header.\n");
> + return AVERROR_INVALIDDATA; // SRgn field value is 0
> + }
> + // SPrgn field
> + // Currently compno cannot be greater than 4.
> + // However, future implementation should support compno up to 65536
> + if (compno < s->ncomponents) {
> + if (s->curtileno == -1)
> + s->roi_shift[compno] = bytestream2_get_byte(&s->g);
> + else {
> + if (s->tile[s->curtileno].tp_idx != 0)
> + return AVERROR_INVALIDDATA; // marker occurs only in first
> tile part of tile
> + s->tile[s->curtileno].comp[compno].roi_shift =
> bytestream2_get_byte(&s->g);
> + }
> + return 0;
> + }
> + return AVERROR_INVALIDDATA;
> +}
> +
> /* Get common part for QCD and QCC segments. */
> static int get_qcx(Jpeg2000DecoderContext *s, int n, Jpeg2000QuantStyle *q)
> {
> @@ -947,6 +973,9 @@ static int init_tile(Jpeg2000DecoderContext *s, int
> tileno)
> comp->coord[1][0] = ff_jpeg2000_ceildivpow2(comp->coord_o[1][0],
> s->reduction_factor);
> comp->coord[1][1] = ff_jpeg2000_ceildivpow2(comp->coord_o[1][1],
> s->reduction_factor);
>
> + if (!comp->roi_shift)
> + comp->roi_shift = s->roi_shift[compno];
> +
> if (ret = ff_jpeg2000_init_component(comp, codsty, qntsty,
> s->cbps[compno], s->cdx[compno],
> s->cdy[compno], s->avctx))
> @@ -1615,9 +1644,9 @@ static void decode_clnpass(Jpeg2000DecoderContext *s,
> Jpeg2000T1Context *t1,
>
> static int decode_cblk(Jpeg2000DecoderContext *s, Jpeg2000CodingStyle
> *codsty,
> Jpeg2000T1Context *t1, Jpeg2000Cblk *cblk,
> - int width, int height, int bandpos)
> + int width, int height, int bandpos, uint8_t roi_shift)
> {
> - int passno = cblk->npasses, pass_t = 2, bpno = cblk->nonzerobits - 1;
> + int passno = cblk->npasses, pass_t = 2, bpno = cblk->nonzerobits - 1 +
> roi_shift;
> int pass_cnt = 0;
> int vert_causal_ctx_csty_symbol = codsty->cblk_style & JPEG2000_CBLK_VSC;
> int term_cnt = 0;
> @@ -1691,6 +1720,19 @@ static int decode_cblk(Jpeg2000DecoderContext *s,
> Jpeg2000CodingStyle *codsty,
> return 1;
> }
>
> +static inline int roi_shift_param(Jpeg2000Component *comp,
> + int quan_parameter)
> +{
> + uint8_t roi_shift;
> + int val;
> + roi_shift = comp->roi_shift;
> + val = (quan_parameter < 0)?-quan_parameter:quan_parameter;
> +
> + if (val > (1 << roi_shift))
> + return (quan_parameter < 0)?-(val >> roi_shift):(val >> roi_shift);
> + return quan_parameter;
> +}
> +
> /* TODO: Verify dequantization for lossless case
> * comp->data can be float or int
> * band->stepsize can be float or int
> @@ -1775,6 +1817,20 @@ static inline void mct_decode(Jpeg2000DecoderContext
> *s, Jpeg2000Tile *tile)
> s->dsp.mct_decode[tile->codsty[0].transform](src[0], src[1], src[2],
> csize);
> }
>
> +static inline void roi_scale_cblk(int x, int y, Jpeg2000Cblk *cblk,
> + Jpeg2000Component *comp,
> + Jpeg2000T1Context *t1)
> +{
> + int i, j;
> + int w = cblk->coord[0][1] - cblk->coord[0][0];
> + for (j = 0; j < (cblk->coord[1][1] - cblk->coord[1][0]); ++j) {
> + int32_t *datap = &comp->i_data[(comp->coord[0][1] -
> comp->coord[0][0]) * (y + j) + x];
This creates a warning during build.
datap is unused in this function
> + int *src = t1->data + j*t1->stride;
> + for (i = 0; i < w; ++i)
> + src[i] = roi_shift_param(comp, src[i]);
> + }
> +}
> +
--
Andriy
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