[FFmpeg-cvslog] mpeg4video: Add Studio DPCM support
Kieran Kunhya
git at videolan.org
Sat Aug 25 23:09:59 EEST 2018
ffmpeg | branch: master | Kieran Kunhya <kieran at kunhya.com> | Sun Aug 19 02:31:42 2018 +0100| [844ff494696e75221e718278139a0db5766ae797] | committer: Paul B Mahol
mpeg4video: Add Studio DPCM support
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=844ff494696e75221e718278139a0db5766ae797
---
libavcodec/mpeg4videodec.c | 91 ++++++++++++++++++++++++++++++++++++++++++++--
libavcodec/mpegvideo.c | 73 ++++++++++++++++++++++++++++---------
libavcodec/mpegvideo.h | 2 +
3 files changed, 146 insertions(+), 20 deletions(-)
diff --git a/libavcodec/mpeg4videodec.c b/libavcodec/mpeg4videodec.c
index 1686ed1001..4c77081237 100644
--- a/libavcodec/mpeg4videodec.c
+++ b/libavcodec/mpeg4videodec.c
@@ -24,6 +24,7 @@
#include "libavutil/internal.h"
#include "libavutil/opt.h"
+#include "libavutil/pixdesc.h"
#include "error_resilience.h"
#include "hwaccel.h"
#include "idctdsp.h"
@@ -36,6 +37,7 @@
#include "profiles.h"
#include "thread.h"
#include "xvididct.h"
+#include "unary.h"
/* The defines below define the number of bits that are read at once for
* reading vlc values. Changing these may improve speed and data cache needs
@@ -1923,10 +1925,91 @@ static int mpeg4_decode_studio_block(MpegEncContext *s, int32_t block[64], int n
return 0;
}
+static int mpeg4_decode_dpcm_macroblock(MpegEncContext *s, int16_t macroblock[256], int n)
+{
+ int i, j, w, h, idx = 0;
+ int block_mean, rice_parameter, rice_prefix_code, rice_suffix_code,
+ dpcm_residual, left, top, topleft, min_left_top, max_left_top, p, p2, output;
+ h = 16 >> (n ? s->chroma_y_shift : 0);
+ w = 16 >> (n ? s->chroma_x_shift : 0);
+
+ block_mean = get_bits(&s->gb, s->avctx->bits_per_raw_sample);
+ if (block_mean == 0){
+ av_log(s->avctx, AV_LOG_ERROR, "Forbidden block_mean\n");
+ return AVERROR_INVALIDDATA;
+ }
+ s->last_dc[n] = block_mean * (1 << (s->dct_precision + s->intra_dc_precision));
+
+ rice_parameter = get_bits(&s->gb, 4);
+ if (rice_parameter == 0) {
+ av_log(s->avctx, AV_LOG_ERROR, "Forbidden rice_parameter\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ if (rice_parameter == 15)
+ rice_parameter = 0;
+
+ if (rice_parameter > 11) {
+ av_log(s->avctx, AV_LOG_ERROR, "Forbidden rice_parameter\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ for (i = 0; i < h; i++) {
+ output = 1 << (s->avctx->bits_per_raw_sample - 1);
+ top = 1 << (s->avctx->bits_per_raw_sample - 1);
+
+ for (j = 0; j < w; j++) {
+ left = output;
+ topleft = top;
+
+ rice_prefix_code = get_unary(&s->gb, 1, 12);
+
+ /* Escape */
+ if (rice_prefix_code == 11)
+ dpcm_residual = get_bits(&s->gb, s->avctx->bits_per_raw_sample);
+ else {
+ rice_suffix_code = get_bitsz(&s->gb, rice_parameter);
+ dpcm_residual = (rice_prefix_code << rice_parameter) + rice_suffix_code;
+ }
+
+ /* Map to a signed residual */
+ if (dpcm_residual & 1)
+ dpcm_residual = (-1 * dpcm_residual) >> 1;
+ else
+ dpcm_residual = (dpcm_residual >> 1);
+
+ if (i != 0)
+ top = macroblock[idx-w];
+
+ p = left + top - topleft;
+ min_left_top = FFMIN(left, top);
+ if (p < min_left_top)
+ p = min_left_top;
+
+ max_left_top = FFMAX(left, top);
+ if (p > max_left_top)
+ p = max_left_top;
+
+ p2 = (FFMIN(min_left_top, topleft) + FFMAX(max_left_top, topleft)) >> 1;
+ if (p2 == p)
+ p2 = block_mean;
+
+ if (p2 > p)
+ dpcm_residual *= -1;
+
+ macroblock[idx++] = output = (dpcm_residual + p) & ((1 << s->avctx->bits_per_raw_sample) - 1);
+ }
+ }
+
+ return 0;
+}
+
static int mpeg4_decode_studio_mb(MpegEncContext *s, int16_t block_[12][64])
{
int i;
+ s->dpcm_direction = 0;
+
/* StudioMacroblock */
/* Assumes I-VOP */
s->mb_intra = 1;
@@ -1945,9 +2028,11 @@ static int mpeg4_decode_studio_mb(MpegEncContext *s, int16_t block_[12][64])
} else {
/* DPCM */
check_marker(s->avctx, &s->gb, "DPCM block start");
- avpriv_request_sample(s->avctx, "DPCM encoded block");
- next_start_code_studio(&s->gb);
- return SLICE_ERROR;
+ s->dpcm_direction = get_bits1(&s->gb) ? -1 : 1;
+ for (i = 0; i < 3; i++) {
+ if (mpeg4_decode_dpcm_macroblock(s, (*s->dpcm_macroblock)[i], i) < 0)
+ return AVERROR_INVALIDDATA;
+ }
}
if (get_bits_left(&s->gb) >= 24 && show_bits(&s->gb, 23) == 0) {
diff --git a/libavcodec/mpegvideo.c b/libavcodec/mpegvideo.c
index f75c0fd9b3..d4d3bea649 100644
--- a/libavcodec/mpegvideo.c
+++ b/libavcodec/mpegvideo.c
@@ -390,6 +390,8 @@ static int init_duplicate_context(MpegEncContext *s)
}
FF_ALLOCZ_OR_GOTO(s->avctx, s->block32, sizeof(*s->block32), fail)
+ s->dpcm_direction = 0;
+ FF_ALLOCZ_OR_GOTO(s->avctx, s->dpcm_macroblock, sizeof(*s->dpcm_macroblock), fail)
if (s->avctx->codec_tag == AV_RL32("VCR2")) {
// exchange uv
@@ -427,6 +429,7 @@ static void free_duplicate_context(MpegEncContext *s)
av_freep(&s->me.score_map);
av_freep(&s->blocks);
av_freep(&s->block32);
+ av_freep(&s->dpcm_macroblock);
av_freep(&s->ac_val_base);
s->block = NULL;
}
@@ -445,6 +448,8 @@ static void backup_duplicate_context(MpegEncContext *bak, MpegEncContext *src)
COPY(blocks);
COPY(block);
COPY(block32);
+ COPY(dpcm_macroblock);
+ COPY(dpcm_direction);
COPY(start_mb_y);
COPY(end_mb_y);
COPY(me.map_generation);
@@ -820,6 +825,8 @@ static void clear_context(MpegEncContext *s)
s->blocks = NULL;
s->block32 = NULL;
memset(s->pblocks, 0, sizeof(s->pblocks));
+ s->dpcm_direction = 0;
+ s->dpcm_macroblock = NULL;
s->ac_val_base = NULL;
s->ac_val[0] =
s->ac_val[1] =
@@ -2132,23 +2139,55 @@ void mpv_reconstruct_mb_internal(MpegEncContext *s, int16_t block[12][64],
TODO: Integrate 10-bit properly into mpegvideo.c so that ER works properly */
if (s->avctx->bits_per_raw_sample > 8){
const int act_block_size = block_size * 2;
- s->idsp.idct_put(dest_y, dct_linesize, (int16_t*)(*s->block32)[0]);
- s->idsp.idct_put(dest_y + act_block_size, dct_linesize, (int16_t*)(*s->block32)[1]);
- s->idsp.idct_put(dest_y + dct_offset, dct_linesize, (int16_t*)(*s->block32)[2]);
- s->idsp.idct_put(dest_y + dct_offset + act_block_size, dct_linesize, (int16_t*)(*s->block32)[3]);
-
- dct_linesize = uvlinesize << s->interlaced_dct;
- dct_offset = s->interlaced_dct ? uvlinesize : uvlinesize*block_size;
-
- s->idsp.idct_put(dest_cb, dct_linesize, (int16_t*)(*s->block32)[4]);
- s->idsp.idct_put(dest_cr, dct_linesize, (int16_t*)(*s->block32)[5]);
- s->idsp.idct_put(dest_cb + dct_offset, dct_linesize, (int16_t*)(*s->block32)[6]);
- s->idsp.idct_put(dest_cr + dct_offset, dct_linesize, (int16_t*)(*s->block32)[7]);
- if(!s->chroma_x_shift){//Chroma444
- s->idsp.idct_put(dest_cb + act_block_size, dct_linesize, (int16_t*)(*s->block32)[8]);
- s->idsp.idct_put(dest_cr + act_block_size, dct_linesize, (int16_t*)(*s->block32)[9]);
- s->idsp.idct_put(dest_cb + act_block_size + dct_offset, dct_linesize, (int16_t*)(*s->block32)[10]);
- s->idsp.idct_put(dest_cr + act_block_size + dct_offset, dct_linesize, (int16_t*)(*s->block32)[11]);
+
+ if(s->dpcm_direction == 0) {
+ s->idsp.idct_put(dest_y, dct_linesize, (int16_t*)(*s->block32)[0]);
+ s->idsp.idct_put(dest_y + act_block_size, dct_linesize, (int16_t*)(*s->block32)[1]);
+ s->idsp.idct_put(dest_y + dct_offset, dct_linesize, (int16_t*)(*s->block32)[2]);
+ s->idsp.idct_put(dest_y + dct_offset + act_block_size, dct_linesize, (int16_t*)(*s->block32)[3]);
+
+ dct_linesize = uvlinesize << s->interlaced_dct;
+ dct_offset = s->interlaced_dct ? uvlinesize : uvlinesize*block_size;
+
+ s->idsp.idct_put(dest_cb, dct_linesize, (int16_t*)(*s->block32)[4]);
+ s->idsp.idct_put(dest_cr, dct_linesize, (int16_t*)(*s->block32)[5]);
+ s->idsp.idct_put(dest_cb + dct_offset, dct_linesize, (int16_t*)(*s->block32)[6]);
+ s->idsp.idct_put(dest_cr + dct_offset, dct_linesize, (int16_t*)(*s->block32)[7]);
+ if(!s->chroma_x_shift){//Chroma444
+ s->idsp.idct_put(dest_cb + act_block_size, dct_linesize, (int16_t*)(*s->block32)[8]);
+ s->idsp.idct_put(dest_cr + act_block_size, dct_linesize, (int16_t*)(*s->block32)[9]);
+ s->idsp.idct_put(dest_cb + act_block_size + dct_offset, dct_linesize, (int16_t*)(*s->block32)[10]);
+ s->idsp.idct_put(dest_cr + act_block_size + dct_offset, dct_linesize, (int16_t*)(*s->block32)[11]);
+ }
+ } else if(s->dpcm_direction == 1) {
+ int i, w, h;
+ uint16_t *dest_pcm[3] = {(uint16_t*)dest_y, (uint16_t*)dest_cb, (uint16_t*)dest_cr};
+ int linesize[3] = {dct_linesize, uvlinesize, uvlinesize};
+ for(i = 0; i < 3; i++) {
+ int idx = 0;
+ int vsub = i ? s->chroma_y_shift : 0;
+ int hsub = i ? s->chroma_x_shift : 0;
+ for(h = 0; h < (16 >> vsub); h++){
+ for(w = 0; w < (16 >> hsub); w++)
+ dest_pcm[i][w] = (*s->dpcm_macroblock)[i][idx++];
+ dest_pcm[i] += linesize[i] / 2;
+ }
+ }
+ } else if(s->dpcm_direction == -1) {
+ int i, w, h;
+ uint16_t *dest_pcm[3] = {(uint16_t*)dest_y, (uint16_t*)dest_cb, (uint16_t*)dest_cr};
+ int linesize[3] = {dct_linesize, uvlinesize, uvlinesize};
+ for(i = 0; i < 3; i++) {
+ int idx = 0;
+ int vsub = i ? s->chroma_y_shift : 0;
+ int hsub = i ? s->chroma_x_shift : 0;
+ dest_pcm[i] += (linesize[i] / 2) * ((16 >> vsub) - 1);
+ for(h = (16 >> vsub)-1; h >= 1; h--){
+ for(w = (16 >> hsub)-1; w >= 1; w--)
+ dest_pcm[i][w] = (*s->dpcm_macroblock)[i][idx++];
+ dest_pcm[i] -= linesize[i] / 2;
+ }
+ }
}
}
/* dct only in intra block */
diff --git a/libavcodec/mpegvideo.h b/libavcodec/mpegvideo.h
index e16deb64e7..bbc6b5646a 100644
--- a/libavcodec/mpegvideo.h
+++ b/libavcodec/mpegvideo.h
@@ -509,6 +509,8 @@ typedef struct MpegEncContext {
int (*decode_mb)(struct MpegEncContext *s, int16_t block[12][64]); // used by some codecs to avoid a switch()
int32_t (*block32)[12][64];
+ int dpcm_direction; // 0 = DCT, 1 = DPCM top to bottom scan, -1 = DPCM bottom to top scan
+ int16_t (*dpcm_macroblock)[3][256];
#define SLICE_OK 0
#define SLICE_ERROR -1
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